1. Emergence of Syntax

2. Introduction  One of the most important concerns of theoretical linguistics today represents the study of the acquisition of language.  By studying language acquisition, we can learn more about the innate structures, Universal Grammar, which drive the process of acquisition.

3.  Research shows: children and adults do not differ with respect to devices for acquiring language structure (the Continuity Approaches) or Children differ in their grammar in comparison to adults, by building language structure (The Structure Building Model).

4.  Even though children talk differently than adults, underlying knowledge of the language structure is the same.

5. Emergence of Functional Categories  Continuity Hypothesis (Hyams 1992)  Lexical elements need to be acquired  Grammatical principles and the Functional Categories are antecedently available to the child, containing null elements.  Children have full grammatical competence and the differences between child speech and adult speech should be attributed to external factors (i.e. developmental).

6.  The Strong Continuity Approach - functional categories are available from the beginning and they are operative when the child starts to produce sentences, children are filling in the pre- existent categories as they mature.  Differences between adult speech and child speech are maturational.  This approach is also called the Maturational Approach (based on lexical learning as the child fills in the preexisting categories).

7. “No Functional Categories” “No Functional Categories” = The Structure Building Model (Radford 1990)  no Functional Categories available at the beginning  grammar is characterized by the absence of the functional categories and the child builds the functional categories as they acquire language.

8. Finite Vs. Non-finite  Parameters are set correctly very early (Wexler: 1998)  Children, at a very early stage, “know” the contrast between finite and non-finite verbs  Both finite and non-finite verbs are used, but finite verbs only occur in finite contexts. In some languages (e.g. English, Dutch, German), children go through an Optional Infinitive (Root Infinitive) stage.

9. Optional Infinitive Stage  Wexler (1998) - the Optional Infinitive Stage is caused by the so called Unique Checking Constraint which prevents a D-feature on DP from checking more than one D-feature on functional categories (Tense and Agreement), therefore forcing either TNS or AGR to be omitted.  The Truncation Theory (Rizzi) claims that in this stage, children do not recognize a Complementizer position in Root clauses (infinitive clauses).  Hoekstra and Hyams (1993) - The Optional Infinitive Stage results from the lack of the number agreement.

10. What are Root Infinitives?  Children produce main clauses containing an infinitive verb, rather than a finite verb  Phenomenon observed in: English, Danish, Dutch, French, German, Russian

11. Examples: a.Dormir petit bébé sleep-Inf little baby ‘Little baby sleep’ b.Mary go. c.Papa have it. d.Dolly like ice-cream.

12. Root Infinitives  The Optional-Infinitive stage - stage in grammatical development when children use root infinitives and tensed verbs as grammatical, in alternation.

13. The Optional Infinitive Stage  The Optional Infinitive stage appears not only in English, but also in all Germanic languages, as well as French and other languages.  Children acquiring German use finite verbs in second position and non-finite verbs in final positions. This is given by the V2 process (V to C movement).

14.  Wexler (1992) - null subjects are the effect of the Optional Infinitive stage, and there is evidence that children use null subjects mainly with non-finite verbs.  In the Optional Infinitive stage, Agr and/or Tense may be omitted. If Agreement is omitted, then there is no NOM case assigned, the subject gets the default case, which is ACC in English.  The lack of Tense licenses PRO, the use of the null subjects.

15. Pattern (Wexler) a). he likes ice-cream [+AGR, +TNS] b). he like ice-cream [+AGR, -TNS] c). him like ice-cream [-AGR, +TNS] d). *him likes ice-cream

16.  Wexler (1998) proposes that the OI stage is caused by the so-called Unique Checking Constraint.  While raising, the subject can only check one D-feature from the Tense or Agreement (assuming that these functional projections have a D- feature associated with them).

17. The Truncation Theory - Rizzi  A child can choose to project all the way up to CP, or he can project just part of the way up.  But he can’t leave anything out from the middle of the tree.  The difference between the child:  the adult takes CP as the root node of any sentence, whereas the child can choose anything as the root node.  The extra constraint requiring CP to be the root is something that emerges maturationally some time before the child’s third birthday.

18. Null Subject Languages  Children acquiring a null-subject language (Italian, Spanish, Catalan or Romanian) – no Optional Infinitive stage, because they make the distinction between finite and non-finite verbs and use correct verbal forms (finite/non-finite) in proper environments.  Torrens (Spanish and Catalan) concludes that children do not undergo an Optional Infinitive stage, they distinguish between finite and non-finite verbs and they produce verbs in correct contexts.

19. Null Subject Languages  Italian children (Guasti 1993) - distinguish between finite and non- finite verbs and the Optional Infinitive stage is not a characteristic of the Italian child language.  Romanian children correctly place the verb forms in the correct distributions.

20. Null Subject Languages  Grinstead (2000) - Spanish and Catalan children - claims that children at a very early stage “lack contrastive use of tense and number morphology”. But this stage ends at around 1;10 and that is when the recordings for the present research studies just started.  Phillips (1995) – if speakers of null- subject languages have Root Infinitives this is happening before the earliest possible recording.

21. Properties of Root Infinitives a. Do not occur in pro-drop Languages b. Occur in declarative Sentences, but not in wh-questions c. Root infinitives are incompatible with auxiliaries

22. Phillips (1995)  Root infinitive clauses are not due to a deficit in syntactic or morphological knowledge.

23.  Root infinitive clauses are fully represented finite clauses in which merger of the verb with inflection has been delayed

25.  Phillips (1995) root infinitives depend on the interaction of the detailed knowledge children have of their target language at a very early age with one specific performance factor: the task of accessing morphological knowledge.  The morphological simplifications – not a reflection of the child’s knowledge of syntax

26.  The ‘root infinitive stage’ lasts for different lengths of time in different children, and individual children use root infinitives with widely differing frequencies  Frequency of root infinitive use drops off gradually over time.

27. Root Infinitives in German and Dutch

28. English