From number agreement to the subjunctive: Evidence for Processability Theory in L2 Spanish

Abstract

This article contributes to typological plausibility of Processability Theory (PT) (Pienemann, 1998, 2005) by providing empirical data that show that the stages predicted by PT are followed in the second language (L2) acquisition of Spanish syntax and morphology. In the present article, the PT stages for L2 Spanish morphology and syntax are first hypothesized after a brief description of PT theory. The results of a corpus of conversational data by L2 Spanish learners (n = 21) are then presented. Implicational scaling confirmed the five stages for the syntax and morphology with 100% scalability. Evidence was also found for the existence of discrete stages 1,2, 3 and 5 for the syntax as well as stages 1–4 for the morphology. Syntax was also found to emerge before morphology for all learners.

Keywords

morphosyntax Processability Theory second language acquisition Spanish

I Introduction

The development of syntax and morphology has often been found to follow predictable routes for second language (L2) learners. Processability Theory (PT) (Pienemann, 1998, 2005) offers a psycholinguistic explanation as to how and why learners’ morphosyntactic development follows similar routes: the main claim of PT is that learnability is restricted by computational constraints of the language processor. As such, learning a language requires the gradual acquisition of language-specific processing procedures based on Levelt’s (1989) speaking model (Pienemann, 2005: 2). This view of language performance is complemented by a theory of grammar, Lexical-functional grammar [LFG] (Kaplan and Bresnan, 1982), which is a model of grammar that reflects many of the psycholinguistic principles prominent in Levelt’s (1989) theory of production.

Much PT research has focused on establishing typological plausibility for a variety of languages (e.g. Mansouri, 2005; Zhang, 2005), although some studies have focused on aspects of the basic assumptions of PT, such as investigating the independent nature of each stage (Jansen, 2008), exploring the role of first language (L1) transfer in PT (Bohnacker, 2006; Håkansson et al., 2002; Pienemann and Håkansson, 2007), and questioning whether the syntax and morphology develop jointly or separately (Dyson, 2009). The stages predicted in PT have been supported cross-linguistically with empirical evidence by learners of German (Jansen, 2008; Pienemann, 1998, 2005), Italian and Japanese (Baten, 2011; Di Biase and Kawaguchi, 2002; Kawaguchi, 2005), English (Pienemann, 1998, 2005; Sakai, 2008; Spinner, 2011), Swedish (Pienemann, 1998; Pienemann and Håkansson, 1999), Chinese (Zhang, 2005), Arabic (Mansouri, 2005), and Danish and Norwegian (Glahn et al., 2001). This article contributes to typological plausibility of PT by applying the processing stages to the acquisition of L2 Spanish syntax and morphology. The goal of this application of PT to Spanish was to first predict stages for Spanish based on the kinds of structures that have already been established for other languages, such as Italian (Di Biase and Kawaguchi, 2002). The stages predicted for Spanish were then tested on a corpus of data from L2 classroom learners of Spanish.

II Overview of PT

PT focuses on one aspect of Levelt’s model of speech production (Levelt, 1989): that of grammatical encoding in the Formulator, whose role is to take the concept of a message and apply the necessary grammatical procedures and phonological encoding before the message is sent to the Articulator. According to Levelt’s model, a fully competent speaker follows a series of procedures in an incremental manner to produce speech: from lemma activation to production of inflected words and full utterances via procedures that work together to produce messages with appropriate syntax and morphology. These procedures are considered to be active for mature language speakers; what PT addresses is how second language learners acquire these procedures. In order to interpret the PT hierarchy for languages of varying typology, a unification grammar, LFG, is used.

LFG in PT serves as a means by which syntactic and morphological structure of languages of various typologies can be exemplified in terms of the main processing procedures depicted by PT. A brief sketch of the main principles of LFG as pertinent to PT follows. The main components of LFG are the lexicon, c-structure (constituent), f-structure (functional) and a-structure (argument). F-structure links the grammatical information with the semantic interpretation to give the sentence meaning. A-structure specifies which argument roles are needed for a given predicate. C-structure represents the surface structure of constituents. The overall relationship between c-structure, a-structure and f-structure is illustrated in Figure 1.

Figure 1.

LFG structure for Luis tiene un perro ‘Luis has a dog’.

In the lexicon, not depicted here, each lexical entry is annotated with various features, such as number, person, or tense that has varying values (e.g. singular, plural, present), which are used to generate sentences. Each lemma includes the information not only as to which arguments it needs and which grammatical roles those arguments have, but also diacritic features such as tense. LFG is the reference point for interpreting grammars of various languages in the PT hierarchy, which has been the focus of much PT research.

III Stages for L2 Spanish

Based on the original version of PT (Pienemann, 1998), the extended version (Pienemann et al., 2005), and prior typological studies of the PT stages (e.g. Pienemann and Håkansson, 1999; Di Biase and Kawaguchi, 2002), the stages shown in Table 1 are hypothesized for Spanish morphology and syntax. Johnston (1995) proposed seven stages for Spanish based on an early version of PT¹ but the intention of this article is to investigate stages for Spanish based on PT (Pienemann, 1998) and the Extended version (Pienemann et al., 2005). In Table 1 the first column shows the PT processing procedures drawn from Levelt’s (1989) speech processing model: lemma access, category procedure, phrasal procedure, S-procedure, and subordinate clause (S’) procedure. The subsequent columns show which morphological and syntactic structures are predicted to be acquired at a given point in time (T).

Table 1.

Processing procedures applied to Spanish word order and morphology.

Procedures and stages	T1	T2	T3	T4	T5
S’-procedure (EmbeddedS) (Stage 5)	–	–	–	–	Inter-clausal agreement (subjunctive) / Subordinate clauses
S-procedure (Stage 4)	–	–	–	Inter-phrasal agreement (-s) / Target word order (SV-inversion)	+
Phrasal procedure (Stage 3)	–	–	Phrasal agreement (-s) / XP-adjunction	+	+
Category procedure (Stage 2)	–	Lexical morphemes (-s) / Canonical word order (SVX)	+	+	+
Word / lemma (Stage 1)	‘words’	+	+	+	+

1 Stages 1 and 2

At Stage 1, learners are limited to producing lemma, i.e. words or formulaic expressions. No exchange of information is possible, and thus no feature matching, or unification. Feature unification is an important component of LFG that is integral to the processing perspective of PT as discussed by Pienemann (1998: 73):

the unification of lexical features, which is one of the main characteristics of LFG, captures a psycholinguistically plausible process that involves (1) the identification of grammatical information in the lexical entry, (2) the temporary storage of that information and (3) its utilization at another point in the constituent structure.

In terms of syntax, at Stage 2, learners begin to produce strings based on canonical word order, which involves a prototypical mapping of the most prominent thematic role, i.e. agent, to the initial position in c-structure, i.e. subject (The Unmarked Alignment Hypothesis; Pienemann, Di Biase, and Kawaguchi, 2005: 229). This analysis assumes a one-to-one correspondence between a- structure, f-structure and c-structure; the process of producing SVO then is a linear process that requires no exchange or storage of information. This is possible because it is assumed that learners are able to define categories such as ‘verb’ and ‘subject’, but mapping is restricted by the inability to unify features. L1 transfer is assumed to play a role at this stage in syntax, because L2 learners can draw on the three levels of structures they use for their L1, although they are not predicted to rely on L1 word order rules at this stage.² Rather, according to the Unmarked Alignment Hypothesis, it is predicted at Stage 2 syntax that L2 learners will start with a default mapping of the agent to the initial position in the phrase. In this case, we would expect a subject-first strategy, SVO, for Spanish. As for morphology at Stage 2, category procedure, the ability to assign a category to the lemma, develops. An example of a category is the feature ‘plurality’; in Spanish, for example, the plural -s would emerge here as the learner becomes able to add ‘s’ to lemmas to indicate plurality, for example, manzanas ‘apples’.

2 Stage 3

For the syntax of Stage 3, PT predicts that learners will be able to front prepositional phrases, wh-words or adverbs before canonical word order. According to Pienemann, this is possible because learners are able to add adjuncts to the initial position in c-structure although they still do not have the ability to modify canonical word order (The Topic Hypothesis; Pienemann et al., 2005: 239). Topicalization and focalization of prepositions or adverbs are common in Spanish. This stage is illustrated in (1).

(1) Por las tardes a veces vamos al cine

The afternoons sometimes we go to the movies.

‘Sometimes in the afternoons we go to the movies.’

Regarding morphology, phrasal procedure should be available at this stage, which means, for example, to produce a phrase such as las manzanas ‘the apples’, the plurality feature of the noun can be stored in the NP-procedure and matched with the determiner phrase. In L2 Spanish at this stage, then agreement should be possible within the same constituent, for example, in attributive adjectives as shown in (2).

(2) tengo los pantalones rojos

Have-I the-masc/pl pants-masc/pl red-masc/pl

‘I have the red pants.’

In (2), the determiner los and the adjective rojos must agree in number and gender with the noun they modify. Example (3) shows the c-structure for the sentence.

(3)

As seen in (3), the items under the NP share the same value for NUM (number) and GEN (gender). Spanish also morphologically marks masculine or feminine gender; however only plurality will be considered, given that gender is dependent on each learner’s lexical entry, which makes the determination of gender marking ambiguous (Pienemann, 1998: 159; Pallotti, 2007). In Spanish, gender marking is largely arbitrary. For example, a learner may produce an item, such as la manzana ‘the apple’, but it is indeterminate whether he or she has learned the phrase as a lexical unit, or is explicitly marking gender grammatically.

3 Stage 4

At Stage 4, s-procedure develops: that is, at this stage, the function of the phrase is determined through appointment rules and sent to s-procedure, where the information is stored as the sentence is developed. Through s-procedure, information can be exchanged across constituent boundaries, and more target-like word order phenomena are found based on language-specific syntactic rules. Up until Stage 4, the acquisition of each stage has been defined by morphological procedures developing along with simplified syntactic procedures. In terms of morphology at Stage 4, inter-phrasal information can be exchanged, which involves the exchange of information across constituent boundaries, e.g. subject–verb agreement in English. For syntax, at Stage 4, we would expect variable word order beyond the simplified syntax at Stages 2 and 3. Although Spanish is pro-drop, the subject is often present for clarification (e.g. when switching references) or for pragmatic emphasis (e.g. for contrastive focus) (Zagona, 2002: 25). Word order in finite declarative sentences and subordinate clauses pattern similarly. When the subject is present, its order is variable, but may be SVO, VOS, or VSO. In wh-questions, the subject is normally required to be post verbal, as in (4). Preposition stranding is not allowed; the constituent including the preposition moves to the beginning before the wh-word, as in (5).

(4) ¿Qué comió Luis?

* ¿Qué Luis comió?

‘What did Luis eat?’

(5) Luis habló con la doctora.

¿Con quién habló?

‘Luis spoke to the doctor.’

‘With whom did he speak?’

Since the canonical word order is subject first and because Spanish allows variability in subject position, examples of post-verbal subjects in declarative finite sentences and interrogatives are the target word order phenomena of interest at this stage. For morphology, at this stage, clitic agreement would be possible as shown in (6).

(6) Luis le da las manzanas a su madre

Luis her-dat/sing gives the apples to his mother-sing

‘Luis gives the apples to his mother.’

This procedure involves feature agreement across constituent structures between the clitic le and its referent a su madre. In (6) the dative clitic le must precede the verb; the referent a su madre ‘to his mother’ is variably present in the sentence. Since the dative pronoun and its referent are both present in the utterance and match for number agreement, this exemplifies a case of inter-phrasal agreement (see Di Biase and Kawaguchi, 2002). As seen in (6), the dative clitic precedes the verb; this is also where accusative clitics are placed. The characteristics of dative and accusative clitics are relevant to both the acquisition of syntax in terms of their word order requirements as well as to the acquisition of morphology given their agreement requirements.

Predicative object agreement is also considered to emerge at Stage 4 for Spanish, as shown in (7).

(7) Los pantalones son rojos

The-mas/pl pants-mas/pl are red-mas/pl

‘The pants are red.’

(8)

The c-structure is shown in (8): the number and gender features of the subject pantalones match those of the object rojos.

4 Stage 5

At the final stage, Stage 5, s-procedure is able to call ‘S’ as a procedure, which means that subordinate clauses can be formed. This involves learners annotating the feature ROOT to complementisers. ROOT distinguishes between subordinate and main clauses, expressed as (ROOT = +) in the main clause and (ROOT = –) in the subordinate clause (Pienemann, 1998: 107, 192). At this point, in subordinate clauses the feature MOOD emerges to mark either subjunctive or indicative mood. Example (9) shows an example sentence with subjunctive morphology.

(9)

Given that there are no specific word order phenomena differentiating main clauses from subordinate clauses for competent speakers of Spanish, for Stage 5, subordinate clause procedure, tokens of subordinate clauses themselves will be analyzed for syntax production in order to determine whether learners can produce subordinate clauses or not. A qualitative analysis will also be given of what kinds of subordinate clauses learners produce, as well as whether any specific word order permutations are associated with subordinate clauses and main clauses produced by these learners. It is also of particular interest in L2 Spanish acquisition whether learners can produce subordinate clauses themselves, given that previous research has suggested that learners of L2 Spanish have trouble producing the syntactic structure required to produce subjunctive morphology (Collentine, 1995). In sum, Stage 5 syntax focuses on word order differences between main and subordinate clauses, and, for morphology, at this stage, learners should be able to mark subjunctive mood in subordinate clauses, as well as number agreement between the main and subordinate clause.

The above-mentioned stages are derived directly from the framework of PT. The overall aim of this study is to test whether these stages exist for the development of syntax and morphology for learners of L2 Spanish. In addition, while many studies have supported the stages of PT for various L2s in the original version of PT, many questions remain in testing the theory. First, no study has looked at the full range of structures for each stage predicted by PT for a single language after Pienemann’s (1998) and Pienemann and Håkansson’s (1999) original corpus-based studies. Empirical research has centered on the development of lexical, phrasal or interphrasal morphemes (Baten, 2011; Di Biase and Kawaguchi, 2002; Glahn et al, 2001; Mansouri, 2005; Zhang, 2005) or on word order rules (Glahn et al, 2001³; Jansen, 2008; Kawaguchi, 2005). Only one recent study – Dyson (2009) –has addressed the question of the interaction between the development of syntax and morphology in English learners by looking at the acquisition of a wide range of structures in L2 English. This study aims to contribute to typological validity of the original and extended versions of PT by looking at the development of syntactic and morphological structures in L2 Spanish by addressing whether the stages predicted above are present for English-speaking L2 learners of Spanish in the order predicted.

IV Method

The data to be analyzed in this study come from the Spanish Learner Language Oral Corpus (SPLLOC; Mitchell et al., 2008) collected by the universities of Southampton, Newcastle and York in the United Kingdom and available in CHILDES (MacWhinney, 2000). It consists of oral data from 60 instructed learners with L1 English. All of the participants have learned L2 Spanish in an instructional setting in the UK. Data from three levels of learners were analyzed: Beginners (N = 7), Intermediate (N = 7) and Advanced (N = 7). The beginning learners (13–14 years old) had experienced approximately 180 hours of Spanish instruction, the intermediate (17–18 years old) 750, and the advanced learners (21–22 years old) had received 895 hours, plus a year abroad. The beginning (Year 9) and intermediate learners (Year 13) were in secondary school, while the advanced were Year 4 university students. Most of the participants were female (n = 17), which according to the authors of the database is representative of the fact that most language learners at the high school and university level are female. Speakers with bilingual background or ‘extensive social contact’ with native speakers were not included in the database.

The data analyzed in this study come from the personal interview portion of a photo description task that involved three parts: describing a picture(s), asking questions about the picture, and a personal interview.⁴ In the interview, a native Spanish speaker asked the participant questions about their current interests, their past activities and their plans for the future. According to the information on the SPLLOC website (http://www.splloc.soton.ac.uk), the tasks were conducted by native speakers of Spanish who had been trained in data elicitation. The interviews were conducted at the schools and were recorded using portable recording devices. Sound files and transcripts in the CHAT format are available on the SPLLOC website and through the CHILDES database (MacWhinney, 2000). A total of 1,225 clauses were analyzed.

1 Coding and data analysis

The transcripts were first organized and coded for the syntactic and morphological features predicted by PT. All utterances were categorized according to the order of syntactic elements (e.g. S for subject, V for verb, O for object, and X for any element) and for morphology (Jansen, 2008: 199). Exclusions were clauses mostly in English or unintelligible clauses. Also excluded were repetitions of the exact same phrase by a single learner; for instance, one beginning learner produced practico la natación ‘I swim’ five times during the course of the short conversation. This clause was only counted once in the overall count of production. In addition, verbs like gustar ‘to like’ were excluded from the syntactic analysis but not the morphological analysis. These verbs have a non-prototypical mapping in that the experiencer (typically subject) and theme (typically object) are reversed: experiencer maps to the object position and the theme to subject position. For example; me gustan las manzanas ‘apples are pleasing to me’ (Pienemann et al., 2005: 223). Therefore, for the purposes of this article, gustar and verbs like it were analyzed just for their interphrasal nature of morphology, e.g. Esther produces porque los chicos les gusta ‘because the boys [Pl] they [Pl] like it’.

The emergence criteria, discussed below, were applied in order to make a judgment as to the learner’s stage, and the overall interlanguage by learner level was statistically analyzed using implicational scaling (Hatch and Lazaraton, 1991). Implicational scaling is a means of interpreting the cross-sectional data of learner’s morphological or syntactic development as representative of an individual learner over time. In PT research, it allows for verification of the hypothesized order and cumulative nature of the stages (e.g. Di Biase and Kawaguchi, 2002; Jansen, 2008). Several statistics are calculated in order to verify the hypothesized order and cumulative nature of the stages as described in Hatch and Lazaraton (1991). First, the coefficient of reproducibility (C of R) shows how well the table predicts how a student would perform based on his/her rank in the implicational table. In order to determine how reliable the development order is in the table, the coefficient of scalability (C of S) is calculated. A coefficient of scalability above.6 is considered to indicate a scalable table (Hatch and Lazaraton, 1991); this is the statistic that is typically reported for implicational scaling, along with the C of R, in order to demonstrate that an implicational table is representative of a developmental pattern.

2 Emergence criteria

Acquisition of each stage is defined by the emergence criteria (Meisel et al., 1981) rather than defined by an accuracy count of structures pertinent to PT. Emergence is a way to measure the first use of a structure in order to determine that a learner has acquired the necessary procedure in order to produce the structure (Pienemann, 1998: 138). However, the emergence criteria is not simply whether the learner has used the structure or not, rather a structure must be shown to be used systematically and productively in order to determine emergence (Pallotti, 2007). A structure being used systematically refers to that at first it could be used randomly; systematic use can be reflected in its being used in a sufficient number of tokens or contexts. Productivity relates to a structure being used with a variety of lexical items, in the case of morphology, or in a variety of contexts, in the case of syntax. For syntax, the emergence criterion is the following:

A non-rote-learned structure is considered to have emerged if a minimum of four⁵ total contexts for the rule are also present (following Pienemann, 1998: 145; Jansen, 2008).

One instance of a syntactic structure in question is considered to be a creative, unanalyzed, productive instance of the structure unless it is a rote-learned or chunked phrase. In Spanish, for example, rote-learned chunks were considered to be phrases such as me gusta ‘I like’ or se llama ‘his/her/its name is’. If a phrase is not considered to be chunked or rote-learned, it is considered to be a productive use of the structure with the further caveat that at least four contexts for application or non-application of the rule also exist (Pallotti, 2007).

For morphology, the item in question must be shown to be used systematically and productively with lexically varied words in a minimum of four contexts (Pallotti, 2007; Pienemann, 1998: 13). The emergence criteria used for the emergence of morphology in this article are as follows:

A rule is considered to have emerged if it is used systematically and productively out of a total of at least four contexts. Evidence that a rule is being used systematically and productively is at least two of any of the following situations (Pallotti, 2007: 271, 375): morphological minimal pairs, lexical variety, or creative constructions.

As with the emergence criteria for the syntax, the rationale for the emergence criteria is that a rule is productive and not a learned lexical item. Morphological minimal pairs are found to occur when the same lexical item, e.g. dog, is marked with the target structure, e.g. dog-s, as well as left unmarked, e.g. dog. Evidence that a rule is used with a variety of lexical items was to find three examples of the structure with three different lexical items: e.g. amigos ‘friends’, exámenes ‘exams’, padres ‘parents’, as well as three different lexical items without the structure, e.g. semana ‘week’, iglesia ‘church’, and fiesta ‘party’. Finally, a creative construction was considered an overgeneralization of a rule when it was not required, for example, in English adding the plural -s to foot instead of producing the irregular plural feet. For more details and examples of coding using emergence criteria, see Bonilla (accepted).

V Results

Table 2 shows the implicational scaling of the syntax and morphology together. The numbers to the right of the dotted line indicate acquisition of both the syntax and the morphology for each stage, while the numbers to the left of the dotted line indicate non-acquisition of the stage. The shaded areas indicate that the syntax has emerged for the stage, but the morphology production did not meet the emergence criterion.

Table 2.

Acquisition of syntax and morphology implicationally scaled for all learners.

Participant	Stage 2		Stage 3		Stage 4		Stage 5
	S	M	S	M	S	M	S	M
Nicole	1	0	0	0	0	0	0	0
Benjamin	7	0	0	0	0	0	0	0
Lily	7	3/3	0	3/3	0	0	0	0
Grace	9	1/1	0	2/2	0	0	0	0
Carly	16	2/2	0	3/3	0	0	0	0
Joseph	7	4/4	1	0/3	0	0	0	0
Ava	15	5/5	7	3/3	0	0	2	0
Ann	7	7/7	9	7/7	0	0	0	0
Denise	10	9/9	7	11/14	0	0	0	0
Dorothy	16	7/7	5	7/7	0	0	0	0
Christopher	17	6/6	7	3/5, > 3	0	0	0	0
Mandy	22	19/19	6	13/12	0	0/1	2	0
Cristina	17	9/9	8	7/8	1	1/1	1	0
Hadleigh	23	11/11	11	14/14	4	1/1	2	0
Emily	48	17/17	10	21/21	1	0	4	0
Paula	73	28/28	36	37/37	1	1/1	9	0
Esther	86	16/16	20	22/22	5	4/4	10	2/2
Shayla	65	30/30	43	19/19	4	7/7	20	1
Kyle	63	26/26	28	31/31	9	6/6	26	3/3
Mary	116	41/41	41	35/35	7	5/6	25	0/1
Michelle	115	51/51	56	64/66, > 1	18	12/12	39	4/4

Notes. Stage 2: SVX and plural -s marking; Stage 3: XP-adjunction and NP agreement; Stage 4: SV-inversion and interphrasal agreement; Stage 5: subordinate clauses, subjunctive and interclausal agreement.

The order and nature of the stages of development of the syntax and morphology will be discussed with examples from the data, first separately for syntax, morphology, then both together. Overall, as illustrated in Table 2, the learners show a clear progression from emergence and high production of Stage 2, SVO, to producing subordinate clauses at Stage 5. The stages emerge in the order predicted; as to the right and above the dotted line, there is no evidence of acquisition of the structures; likewise, to the left, there is evidence of acquisition of the structures. The C of R is 1.0, as is the C of S, which shows that this table is 100% scalable, i.e. the stages are acquired in the order predicted. As for evidence that each of the four stages are indeed stages and acquired one-by-one, there is evidence for each of the five stages predicted.

Stage 1, Lexical items: Nicole is at Stage 1; she is the only learner that does not show evidence for acquisition of Stage 2, as she only produces one clause with a subject and verb, which is not enough evidence to show emergence of this stage.

Stage 2, SVO: Benjamin, Lily, Grace, and Joseph produce VO or VX clauses, but produce no clauses with initial adjuncts, a Stage 3 procedure. These learners produced mainly VO or VX clauses (40/45 clauses, or 88.9%). For example, Grace produces juego en ordenador ‘(I) play on the computer’. Overall, subjects are rarely produced, as almost all Stage 2 clauses produced are VO or VX (661/723 or 91.4%).

Stage 3, XP-adjunction: Ann, Denise, Dorothy, and Christopher produce VO, VX, or adjunct-initial clauses. The learners at Stage 3 (e.g. Dorothy and Christopher) produced mostly VO or VX clauses as well as XP-adjunction. For example, Dorothy produces a VX clause, fui para cuatro semanas ‘(I) went for four weeks’, as well as an XP-adjunct clause en septiembre iré al escuela de música ‘in September (I) will go to the music school’. Ava, Mandy and Cristina produce Stage 3 topicalized clauses, and are also are beginning to produce Stage 4 and Stage 5 clauses.

Stage 4, SV-inversion / Clitic placement: Hadleigh has acquired Stages 1–4, and is starting to produce Stage 5 structures. For example, she produces interphasal agreement by matching plurality with a predicative adjective: la s cultura s son ah tan diferente s ‘the cultures are so different’.

Stage 5, Subordinate clauses: Emily, Paula, Esther, Shayla, Kyle, Mary and Michelle all produce subordinate clauses. The most advanced learners produced VO or VX clauses, XP-adjunction, SV-inversion and clitic placement, and subordinate clauses (e.g. Shayla and Kyle), as predicted by PT. For example, Shayla produces a pre-verbal dative clitic: fui a una academia de inglés y les pregunté ‘I went to an English academy and to them I asked’. She also produces subordinate clauses, e.g. me gusta mezclar con la gente que no conozco bien ‘I like to mix with people that I do not know well’. As seen in Table 2, even as learners develop other means of arranging syntactic elements, the majority of clauses (723/1237, or 58%) remain VO or VX.

Overall, several learners are found to be at either Stage 2, 3, 4, or 5 with no evidence of having acquired subsequent stages.

A more detailed analysis of word order in subordinate clauses and which kinds of subordinate clauses these learners produced follows in order to shed more light on the differences between main clauses and subordinate clauses. Of the 144 complex sentences produced by these learners, 28 have explicit subjects in the main clause or the dependent clause. Of these 28 subjects, only 8 appear in the main clause, while 20 appear in the dependent clause, e.g. ehm # eh Jessy pienso que [/] que Jessy es mi favorita porque ehm ‘um Jessy I think that that Jessy is my favorite because um …’ (Mandy). Of these 28 subjects, all but 2 are pre-verbal. This tendency for SV word order mimics the results from non-complex sentences found in the rest of the data, which shows that these learners are not marking subordinate clauses differently in terms of the syntax, which is expected in target-like Spanish. The two post-verbal subjects are found in dependent clauses. Both are examples of target subject / verb inversion: iba a preguntarla cuánto [/] cuánto costaba la chaqueta … ‘I was going to ask her how much cost (V) the jacket (S) [the jacket cost]’ (Michelle). The other example is: espero que vengan mis padres para recogerme sí # en coche ‘I hope that come (V) my parents (S) to pick me up in car’ (Mary). Of the pre-verbal subjects, all but one are target-like: no sé qué la gente hace ‘I don’t know what the people (S) do (V)’ (Paula). In sum, these advanced learners that produce subordinate clauses show variations in word order in subordinate clauses that are mostly target-like, which indicates that they have knowledge of target phrase structure rules in main clauses as well as subordinate clauses.

In sum, all evidence points towards learners acquiring each stage of syntax in a step-like fashion, in the following implicational order: word/lemma > category procedure (SVX/VX) > phrasal procedure (XP-adjunction) > S-procedure (SV-inversion / clitic placement) > subordinate clause procedure (subordinate clause).

VI Morphology

As illustrated in Table 2, the data for the morphology are also 100% scalable, i.e. C of S is 1.0 and C of R is 1.0, which, along with the observations for the development of word order, indicates an implicational relationship between the stages in morphological development. As for the progression from stage to stage, the following observations are found:

Stage 1, Lexical Items: Nicole, Benjamin, Grace, Carly, and Lily are at Stage 1 but not Stage 2, although for Grace, Carly, and Lily, Stages 2 and 3 are beginning to emerge. The least advanced learners, Nicole and Benjamin, produce no plural -s morphology or contexts for plural -s, but only isolated lexical items, a Stage 1 procedure. Beginning learners Grace, Carly, and Lily are starting to produce Stage 2 plural -s as well as some NP agreement, but they do not meet the emergence criteria in order to be considered Stage 2 or 3. For example, Grace only produces one case of plural morphology, amigas, and two cases of phrasal morphology, mis amigas ‘my friends’ and mis deberes ‘my homework’. Carly is closer to meeting the emergence criteria than Grace for phrasal morphology: she produces amigos ‘friends’, muchas cosas diferentes ‘many different things’, and *las muchas cosas diferentes ‘the many different things’. The inclusion of ungrammatical las suggests that Carly has learned the phrase muchas cosas diferentes as an unanalyzed chunk.

Stage 2, Plural -s: Joseph and Ava both show acquisition of Stage 2 plural -s, but not Stage 3, NP-agreement. Joseph, for example, meets the criteria for plural -s, but does not yet mark number on determiners or adjectives, a stage 3 operation. He fails to produce plural -s marking on three lexical items: *mi hermanos ‘my brothers’, *mi hermanas ‘my sisters’, and mi vacaciones ‘my vacations’.

Stage 3, NP-agreement: Christopher, Dorothy, Ann, Denise, Mandy, Cristina, Hadleigh, Emily and Paula mark both plurality (Stage 2) and NP-agreement (Stage 3), but have not yet acquired Stage 4.

Stage 4, Predicative agreement / Object agreement: Esther, Shayla, Mary, and Kyle mark predicative adjectives or objects at Stage 4, but do not yet have enough instances of Stage 5, subjunctive marking. For example, Esther produces the following four cases of interphrasal agreement in the following examples:

(10) pues en la mañana ah yo estaba encargada de # como # ah hacer actividades con los niños ayudala@n [//]ayud(ándoles) [/] ayudándoles a [/] a hacer los deberes del colegio y.

‘so in the morning ah I was in charge of how doing activities with the kids (Pl) helping helping helping them (Pl) to do their schoolwork.

(11) somos todos rubios hablamos ingles somos muy fríos

‘we (Pl) are all blonde (Pl) we speak English (we) are very cold (Pl)

(12) los chicos les gusta

‘the boys (Pl) they like (it) (Pl)

Esther shows just four cases of interphrasal agreement, which makes her case borderline for emergence or not. However, a review of the examples shows that this learner clearly uses interphrasal agreement with four different adjectives and verbs. Strictly speaking, given that two cases in (7) share the same subject, todos, it could be argued that the context is not varied enough; however, given the variety of the other examples, e.g. marking plurality on the indirect object pronoun cliticized to the infinitive in (6) and with gustar in (10), interphrasal agreement was determined to have emerged for Esther.

Stage 5, Subjunctive / Relative clauses: Several learners are starting to produce subjunctive marking (e.g. Kyle and Esther), a Stage 5 procedure. One learner, Michelle, has almost acquired Stage 5 morphology; this learner marked the subjunctive in 2/2 contexts as well as inter-clausal agreement in 2 cases, e.g. y *habían depen(dientes) [//] pues dependistas@n que eran españolas y … ‘and there were salespeople (pl) well salespeople (fem, pl) that were Spanish (fem, pl). In this case, Michelle has marked salespeople with plural agreement between the main clause and the relative clause. This learner used four different Stage 5 rules in four varied lexical contexts, but multiple, i.e. more than four different Stage 5 contexts were left unmarked for subjunctive or inter-clausal agreement. This production only satisfies one of the two requirements for emergence as outlined in the methodology section. Another situation, such as morphological minimal pairs, a creative construction, or more lexical variety would have to be present to determine emergence of this structure for Michelle. Overall, there is evidence by multiple learners for Stages 1, 2, 3, and 4. There is evidence that Stage 5 is beginning to emerge for several learners (Esther, Mary, Kyle, and Michelle).

Next, the emergence of the syntax and morphology across all learners combined will be looked at in order to see if the stages continue to emerge in the order predicted. Counter-evidence to PT would be to find evidence that a learner has skipped a stage; to illustrate, that a learner has acquired Stage 4 morphology, Stage 2 syntax, and neither Stage 3 syntax or morphology, i.e. Stage 3 has been skipped. There were no cases where the morphology had emerged but not the syntax. Moreover, the shaded areas indicate that the syntax and morphology do not emerge simultaneously. Rather, without exception, syntax emerges first when only one of the two has emerged, in other words, in no case has the morphology emerged before the syntax. To illustrate, for learners Benjamin, Lily and Grace, we can see evidence of emergence of Stage 2, SVO, but there is not enough evidence of emergence of the morphological procedures. For three of the more advanced learners (namely, Hadleigh, Emily and Paula) there is not enough evidence to determine emergence of the last two stages for the morphology, while the syntactic phenomena for the last two stages have clearly emerged. This is not counter-evidence to the order of acquisition of stages predicted by PT: although Stage 5 syntax has emerged before Stage 4 morphology for Hadleigh, Emily, and Paula, which potentially shows a ‘skipped’ stage, since Stage 4 syntax has emerged, then it cannot be concluded that any stages have been skipped. Rather, the conclusion is that the learner can process both Stages 4 and 5, but simply has not yet made use of all the structures available at Stages 4 and 5. Indeed, a look at the next three learners (Esther, Shayla and Kyle), the morphology production appears to ‘catch-up’ as there is evidence of Stage 4 morphology as well as Stage 4 and 5 syntax. At Stage 5, the last four learners (Esther, Shayla, Kyle, and Mary) clearly produce a high number of subordinate clauses, but few cases of and contexts for the subjunctive.

On the whole, this dataset represents each developmental stage of the PT hierarchy, as there are learners at who are clearly at a certain developmental stage. Evidence for the stage-like nature of development exists at Stages 2, 3, 4 and 5 by multiple learners, with the exception that only one learner was at Stage 1. However, the syntax and morphology are not found to emerge simultaneously across the board for all learners; rather, syntax overall is found to emerge before the morphology.

VII Discussion

This study aimed to address the development of Spanish syntax and morphology by applying the PT stages to a cross-sectional corpus of learner data. The stages of the syntax will first be discussed, followed by a discussion of the morphology, then both the syntax and morphology.

1 Syntax

The five stages predicted for the syntax were found to emerge in an ordered manner: canonical word (VO or VX) > XP-adjunction > SV-inversion / clitic placement> subordinate clause. Implicational scaling clearly verified the order of the stages with 100% scalability. Most studies on PT have found such a strong fit (e.g. for L2 German and English, Pienemann, 1998; for L2 German, Jansen, 2008). The first stage, canonical word order was predicted to be subject first; however, the results showed that learners rarely explicitly express the subject. For all learners, the majority of the utterances were VO or VX (661/740 or 89.3%). These results add to the body of research that has shown that non-pro-drop first language speakers learning a pro-drop language do not necessarily transfer the word order from the L1 (e.g. Di Biase and Kawaguchi, 2002; Liceras and Díaz, 1999). The production of almost exclusive null-subject phrases by the learners in this article appears to contradict the Unmarked Alignment Hypothesis, as learners do not produce a subject at c-structure. Instead, the initial position is filled by the verb. One possibility is that learners pass through a subject-first stage quickly until they start to incorporate some morphology into their interlanguage, but there is no evidence in this dataset that this might be the case. This issue of null subjects will be discussed further below along with the issue of verbal morphology.

At the third stage, XP-adjunction, learners consistently began to front prepositional phrases and other adjuncts before the verb or before the subject (e.g. Ann or Denise). At the fourth stage, SV-inversion / clitic placement, one learner, Hadleigh, had acquired Stage 4, SV-inversion and clitic placement, but not Stage 5, Subordinate clauses. Overall, the production of Stage 4 structures was relatively low compared to the other stages. This could be due to the fact that Spanish is pro-drop; since learners rarely produced subjects, it was less likely to find examples of SV-inversion. In fact, the majority of the evidence that learners had acquired Stage 4 (S-procedure) were the dative or accusative clitic pronouns that had been placed before the verb. Another limitation for Stage 4 is that no questions were in the dataset, which would have been an important source of evidence for knowledge of the target word order. For Stage 5, many learners were found to produce subordinate clauses with mostly target-like word order, including a few examples of target subject verb inversion. Overall, abundant evidence was found for Stage 5, subordinate clauses, which are fairly common and also highly necessary in speech, while post-verbal subjects are highly variable and dependent on semantics and pragmatics. This perhaps constitutes even stronger evidence for PT, because even with the limited evidence for Stage 4 compared to the abundant evidence for Stage 5, the stages are still upheld.

One area of interest for a future study involves relative clause formation given their syntactic and morphological consequences. Of the 144 subordinate clauses produced by these learners, 46 are relative clauses, the majority of which are subject or direct object relative clauses. One learner produces an example of relativization of a prepositional phrase in which she fails to move the preposition: sí pero creo que los [/] los niños que yo trabajaban CON ehm dormían en una casa … ‘Yes but I think that the children that I worked with ehm slept in a house’. In this case, the preposition con should remain with que. More precisely elicited data targeting the formation of relative clauses would be informative for this aspect of subordinate clause syntax.

2 Morphology

For the morphology, implicational scaling showed the hypothesized order to be upheld with 100% scalability: plural -s > NP-agreement > object agreement / predicative agreement. While the Stage 5 subjunctive had not yet emerged, it was close to meeting the emergence criteria for several learners. As for the results for the syntax, other studies on morphology acquisition have also shown strong scalability (for Arabic, Mansouri, 2005; for Chinese, Zhang, 2005).

The first two stages, plural -s as a lexical marker and NP-agreement as phrasal agreement, are found in the order predicted for all learners. The next stage, interphrasal agreement, has emerged for the most advanced learners (Esther, Shayla, Mary, Kyle and Michelle) while a handful of learners do not produce enough examples of this structure in order to consider its emergence (Mandy, Cristina, Hadleigh, and Paula). The final stage predicted was that of the use of the subjunctive marker in subordinate clauses and agreement across clausal boundaries. Only one learner, Michelle, produced enough examples of both structures in order for this stage to be considered close to emerged; however, as discussed previously, the subjunctive mood is only required in certain contexts in subordinate clauses. The fact that few learners produce could be reflective of the fact that they avoid or are unaware of the contexts for the subjunctive mood. Importantly, however, the advanced learners were found to be capable of producing subordinate clauses before they begin to produce isolated instances of the subjunctive mood. Overall, the results show evidence for independent stages 1,2,3, 4 and 5 in the acquisition of morphology.

An area for further discussion on Spanish morphology is subject/verb agreement, especially in relation to the early null subject occurrences. In this study, with the exception of the least advanced learner, Nicole, who only produces lexical items (Stage 1, ‘lemma access), all learners produce some verbal morphology as well as null subjects. Subject/verb agreement is not considered interphrasal agreement for Spanish as it has been for other languages, such as English. From an LFG and PT perspective, Di Biase and Kawaguchi (2002) and others (see Vigliocco et al., 1996; Di Biase and Kawaguchi, 2002; Mansouri, 2005) have argued that pro-drop languages such as Spanish achieve subject/verb agreement through feature unification. In LFG, the verb is considered to have features with varying values, but, importantly, does not need to exchange information with other constituents, which means that it is not considered an inter-phrasal procedure in PT. For example, as Mansouri (2005) discussed for Arabic, each affix, e.g. first person –o in Spanish hablo ‘I speak’, is assumed to be lexically listed with an attribute (PRED) that specifies null subjects (PRO). In addition, each affix must be annotated for other grammatical features, such as number agreement (AGR NUM), and person agreement (AGR PERS) (see Mansouri, 2005: 133). The L2 acquisition of subject/verb agreement then is dependent on lexical acquisition, feature specification, and finally feature unification. From a PT perspective, one possibility is that this procedure is categorical, like Stage 2 plural -s. This is possible because affixes are hypothesized to be annotated for grammatical features, such as person and number agreement. In that sense, learners could begin annotating features as soon as they begin to develop categories for individual lexical entries, including verbs. This could explain the early production of inflected verbs and null subjects for Spanish by beginning learners because some inflection could happen very early in acquisition to varying degrees of accuracy.

3 Syntax and morphology

The interaction between the development of syntax and morphology – i.e. whether syntax emerges before morphology or morphology before syntax – has been relatively unexplored in PT research, although it has been widely studied from other perspectives in second language acquisition research, particularly from generative approaches that have questioned the degree to which Universal Grammar (UG) categories may be available in L2 acquisition. Research has questioned whether learner variability in production of overt morphological forms is due to the absence of syntactic categories to produce such items, for example, the minimal trees hypothesis (Vainikka and Young-Scholten 1994, 1996) and the valueless features hypothesis (Eubank, 1993, 1994), or rather due to a fundamental problem in marking these items even though the syntactic categories are represented on an abstract level, namely, the missing surface inflection hypothesis (Haznedar and Schwartz, 1997; Prévost and White, 2000). In PT research, Dyson (2009) argued for a dual role of access to UG categories and acquisition of PT processing procedures to explain developmental patterns. Dyson found that PT Stages 2, 3 and 4 syntactic structures emerged before the corresponding morphological ones in a longitudinal study of two English as a Second Language (ESL) learners. Similarly, in the present study, syntactic structures were also found to emerge before morphological ones at all stages. For instance, learners first produced Stage 2 canonical word order before showing production of Stage 2 lexical morphemes. At Stage 3, learners begin to produce topicalized clauses first, and then begin to show evidence of phrasal agreement within the noun phrase. Dyson argued that the nature of the syntactic categories produced by the two learners in her study reflect a gradual acquisition of functional UG categories, which in turn provide contexts for the PT processing procedures for the morphology to follow. Dyson’s perspective is that Stages 2 and 3 are morphological in nature, since only simplified syntactic procedures are available at these stages. Therefore, Dyson proposes that the syntax occurring before morphology at these stages could be due to other mechanisms, such as access to UG. However, the evidence that syntax has emerged before morphology at Stages 2 and 3 in these two studies is not directly contradictory to the predictions of PT. PT claims that learners acquire the ability to process each stage in a hierarchical fashion; however, a learner does not necessarily produce all processable structures at a given stage once that stage is reached. In that sense, PT does not claim explicitly that either syntax or morphology should emerge in any particular order in relation to each other. Learners could show emergence of one or more Stage 2 syntactic or morphological structures, but do not have to show evidence of all the structures at a given stage. It may also be the case, as Dyson (2009) discussed, that some learners are more inclined to mark morphology, while others may rely more on syntax. It is possible that the syntax emerging before morphology found in these two studies is indicative of a broader cross-linguistic developmental pattern, but the patterns may also be subject to variability within stages across learners. For instance, Bonilla (accepted) analyzed production data by beginning classroom learners of Spanish performing a story re-tell and personal interview task, and found that the least proficient learners showed emergence of morphology before syntax at Stages 3 and 4. The author hypothesized that this pattern is likely reflective of the influence of classroom instruction on lexical items and number agreement within and across the phrase. The context of learning, e.g. naturalistic vs. more formal settings, along with the nature of the eliciting task, are issues for further consideration in research on the developmental patterns of syntax and morphology.

VIII Conclusions

This article aimed to apply the universal developmental stages predicted by PT to the acquisition of morphosyntactic phenomena in Spanish. Using the criteria set forth in PT for the stage-like development of syntax and morphology as governed by the gradual acquisition of speech processing procedures and considering previously established PT structures cross-linguistically, specific stages were predicted for the production of Spanish by classroom learners with L1 English and tested on a corpus of learner data.

The order and cumulative nature of stages for the syntax (SVO, XP-adjunction, SV-inversion / clitic agreement, and subordinate clauses) as well as for the morphology (plural -s, number marking, predicative adjectives / object agreement, and subjunctive marking) were upheld by implicational scaling with a fit of 100%. These stages were found to emerge in a set order for all learners, thereby upholding the developmental sequence predicted by PT. As to whether the stages are indeed acquired one-by-one, evidence of transitions from Stages 1 to 2, Stage 2 to 3, and Stage 3 to 4 and 5 were found for the syntax. No evidence was found for an independent stage 4 for the syntax. The predictions for Spanish word order were based off of the general principles predicted by PT, as no previous study has analyzed the development of word order of a Romance language from the PT framework. Importantly, the canonical word order (Stage 2) for L2 learners of Spanish was found to be VO, as learners rarely produced explicit subjects. This result provides potential counter-evidence to the Unmarked Alignment Hypothesis (Pienemann et al, 2005). For the morphology, transitions between all stages were found by multiple learners. The only exception is from Stage 4 to Stage 5, as not enough contexts were produced to determine acquisition of Stage 5 for any learners. The stages predicted for the morphology for the most part reflect and support Di Biase and Kawaguchi’s (2002) result for development of second language Italian. The syntax was found to emerge before the morphology, but the overall implicational hierarchy was still found to be upheld with 100% scalability when the syntax and morphology were combined.

This article provides important cross-linguistic support for PT, as no previous study has applied PT stages to acquisition of Spanish. Points to consider in future analyses are the gaps in the present analysis where not enough contexts existed in order to determine adequately acquisition or non-acquisition of the stages. Another point for further research is to test these stages with other kinds of oral tasks; a starting point would be the SPLLOC database that has a variety of oral tasks besides the conversational interview analyzed in this article. This line of research would also relevant to the Steadiness Hypothesis, which states that a learner’s stage should not vary by tasks that are based on the same skill (Pienemann, 2005: 44). Another topic that remains to be addressed in the acquisition of Spanish morphosyntax is the place of subject/verb agreement in the PT hierarchy. Almost all learners in this study were capable of producing inflected verbs for tense and person; it remains a question of future analysis whether beginning learners mark subject/verb agreement and tense productively or base their production on memorized lexical items. A detailed distributional analysis (Pienemann, 1998: 157) would be necessary to accurately classify whether learners productively mark verbal morphology or are producing memorized lexical items. Overall, the results of this study illustrate five stages in acquisition of Spanish syntax and morphology, by applying PT theory to Spanish grammar and discussing further syntactic and morphological phenomena for future analysis

Footnotes

Acknowledgements

This work was completed at part of my dissertation research in the Department of Linguistics at the University of Pittsburgh. I would like to thank my committee, especially my advisor, Yasuhiro Shirai, and committee members Alan Juffs, Marta Ortega-Llebaria, and Mariana Achugar. I am also grateful to Nausica Marcos Miguel and Michael K. Olsen for reviewing earlier drafts of this work. I also want to thank the editors and reviewers for their thoughtful comments that greatly improved an earlier version of this manuscript. All remaining errors are my own.

Declaration of Conflicting Interest

The author declares that there is no conflict of interest.

Funding

When the majority of the work for this article was carried out, the author held an Arts and Sciences Fellowship from the University of Pittsburgh, USA.

Notes

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