Week 2b. Root infinitives - PowerPoint Presentation

Slide1

Week 2b. Root infinitives

CAS LX 500A1

Topics in Linguistics: Language Acquisition

Slide2

Syntax 101Initially, children start off producing basically one-word utterances.

Though not impossible (comprehension), it is difficult to conclude much about syntactic knowledge at this stage.

Somewhere around one and a half years, kids will start putting words together: Syntax… of a sort.

Papa have it

(Eve 1;6)

Marie go.

(Sarah 2;3)

Eve gone

(Eve 1;6)

Eve cracking nut.

(Eve 1;7)

Kitty hiding

(2;10)

Fraser not see him

(Eve 2;0)

Slide3

Eve talk funnyThis is recognizably related to English, and even comprehensible, but it’s not the way adults talk.

3sg

-s

often missing.

Past tense -

ed

often missing.

Auxiliaries

have

,

do

, and

be

often missing.

In general, it seems like the grammatical (functional) bits that are missing. Actually, it’s kind of specific type of functional bit.

Slide4

My need teaThe things that seem to be missing are actually things that all were considered part of “INFL” (a.k.a. “I”, a.k.a. “T”). Tense and subject agreement.

Even if syntactic theory has gone on to the view that there are multiple functional heads there (AgrSP, TP, AgrOP), it’s still the

functional

part of the tree (vs.

lexical

).

Slide5

Small Clause Hypothesis

A very natural suggestion to make about kids’ syntax at this stage is that it lacks the functional layers of structure.

The sentences are “small clauses”—just the VP, and the NP.

Various people have run with this idea. For example, Radford, Vainikka.

“Structure building” approach to acquisition of syntax.

Slide6

Small Clause HypothesisRadford (1990, 1995), Early Child English

Kids’ syntax differs from adults’ syntax:

kids use only lexical (not functional) elements

structural sisters in kids’ trees always have a

q

-relation between them.

VP

“

Small Clause NP q V’ Hypothesis” man V q NP chase car

Slide7

Small Clause HypothesisAdults: CP—IP—VP

Kids: VP

adult syntax ≠ child syntax

Absence of evidence for IP:

No modals (repeating, kids drop them)

No auxiliaries (

Mommy doing dinner

)

No productive use of tense & agreement (

Baby ride truck

, Mommy go, Daddy sleep)Absence of evidence for CP:no complementizers (that, for, if)no preposed auxiliary (car go?)no wh-movement (imitating where does it go? yields

go?; spontaneous: mouse doing?)

kids bad at comprehending wh-object questions (out of canonical order). (—What are you doing? —No.)

Slide8

Small Clause HypothesisAdults: CP—IP—VP

Kids: VP

adult syntax ≠ child syntax

Absence of evidence for DP:

no non-

q

elements

no expletives (

raining

,

outside cold)no of before noun complements of nouns (cup tea)Few determiners (Hayley draw boat, want duck, reading book)No possessive ’s, which may be a D.No pronouns, which are probably D.See also Vainikka (1993/4) for a similar proposal.

Slide9

To sleep little baby

Turns out kids talk funny around this time in lots of languages. A particularly popular funny way to talk is to use infinitives.

Danish:

køre bil

‘drive[inf] car’

German:

Thorstn das habn

‘T that have

inf

’

French:

Dormir petit bébé ‘sleepinf little baby’Dutch:Earst kleine boekje lezen ‘first little book readinf’Further evidence for missing functional projections?

Slide10

Sleeps babyWell, but maybe not. At the very same time as they’re using these superfluously infinitive verbs, they are also using finite verbs.

Well, yeah, sure, but they

hear

finite verbs. But they don’t have the clause-structural support for it yet (so they don’t know the verbs are finite or not—that’s information one gets from INFL). It’s just that you can pronounce ‘sleep’ either as

dort

(sleeps) or as

dormir

(sleep). Right? Yes?

Well, it’s easy to check. See if they can tell the difference. See if they make errors—finite verbs come in various kinds, do they use 1st person agreement when they should have used 3rd?

Slide11

Do kids get I/T?Radford points out that the overt realization of I (T) is often missing (morphology, modals, auxiliaries).

But is it random? Are kids just arbitrarily using tense morphology when they do?

When tense is there, does it act like tense would for an adult?

Do kids differentiate between tensed and infinitive verbs, or are these just memorized Vs at this point?

If kids differentiate between tensed and infinitive verbs, there must be some grammatical representation of tense.

Slide12

Adult GermanPoeppel & Wexler (1993). Data: Andreas (2;1, from CHILDES).

Adult German is SOV, V2

The finite verb (or auxiliary or modal) is the second constituent in main clauses, following some constituent (subject, object, or adverbial).

In embedded clauses, the finite verb is final.

V2 comes about by moving the finite verb to (head-initial) C.

Slide13

German clause structure

This “second position” is generally thought to be C, where something else (like the subject, or any other XP) needs to appear in SpecCP.

This only happens with finite verbs. Nonfinite verbs remain at the end of the sentence (after the object).

—

I



IP

DP

DP

V



VP

kaufte

Hans

C+I

C



CP

—

—

den Ball

Slide14

German clause structure

Things other than subjects can appear in “first position”.

When the tense appears on an auxiliary, the verb stays in place.

hat

I



IP

DP

DP

V



VP

gekaufte

den

Ball

C+I

C



CP

—

Hans

V

Slide15

What to look forin Child German

Poeppel & Wexler found that Andreas will sometimes use a finite verb, sometimes a nonfinite verb.

In adult German: finite verbs move to 2nd position, nonfinite verbs are clause-final.

Does this also happen in kid German?

Look for a correlation between finiteness and verb position:

ich mach das nich du das haben

I do that not you that have

Slide16

Results

There is a strong contingency.

Conclude

:

the finiteness distinction is made correctly (at the earliest observable stage).

Conclude:

children

do

represent tense.

Andreas: 33 finite, 37 nonfinite verbs. 8 in both: finite, V2; nonfinite final. Remaining verbs show no clear semantic core that one might attribute the distribution to.

+finite

-finite

V2, not final

197

6

V final, not V2

11

37

Slide17

Verb positioning =functional categories

In adult German, V2 comes from V



I



C

.

If we can see non-subjects to the left of finite verbs, we know we have

at least one functional projection (above the subject, in whose Spec the first position non-subject goes).F

FP

Subject

V



VP

Object

F+V

—

—

Slide18

Is it really V2 (not SVO)?V2 (German) is different from SVO in that the preverbal constituent need not be the subject.

Is Andreas really using adult-like V2 (not SVO)?

Look at what’s preverbal:

Usually subject, not a big surprise.

But 19 objects before finite V2

(of 197 cases, 180 with overt subjects)

And 31 adverbs before finite V2

Conclude

:

Kids basically seem to be acting like adults; their V2 is the same V2 that adults use.

Slide19

Full Competence Hypothesis(Poeppel & Wexler 1993)

The morphosyntactic properties associated with finiteness and attributable to the availability of functional categories (notably head movement) are in place.

The best model of the child data is the standard analysis of adult German (functional projections and all). The one exception:

Grammatical Infinitive Hypothesis:

Matrix sentences with (clause-final) infinitives are a legitimate structure in child German grammar.

Slide20

CPThe Full Competence Hypothesis says not only that functional categories exist, but that the child has access to the

same

functional categories that the adult does.

In particular, CP should be there too.

Predicts what we’ve seen:

finite verbs are in second position only

(modulo topic drop leaving them in first position)

nonfinite verbs are in final position only

subjects, objects, adverbs may all precede a finite verb in second position.

Slide21

Comparing FCH to SCHSCH (Radford, et al.) pointed to lack of morphological evidence for CP.

But they also tend not to use embedded clauses. Which causes which?

But P&W showed

syntactic

evidence for a functional category (V2 with finite verbs) to which V moves. Adults use CP for this.

finite verb is second

non-subjects can be first

“Absence of evidence ≠ evidence of absence.”

Andreas uses agreement correctly when he uses it—adults use IP for that.

Slide22

Is it really CP and IP?Or just FP?

Can we get away with

only one

functional category?

The word order seems to be generable this way so long as F is to the

left

of VP.

subject can stay in SpecVP

V moves to F

non-subject could move to SpecFP.

…though people tend to believe that IP in German is head-

final (that is, German is head-final except for CP). How do kids learn to put I on the right once they develop CP?

Slide23

Is it really CP and IP?

Empirical argument for CP & IP:

negation

and

adverbs

mark the left edge of VP.

A subject in SpecVP (i.e. when a non-subject is topicalized) should occur to the

right

of such elements (if there’s just an FP).

So, look for non-subject-initial sentences with negations or an(other) adverb.

There were 8 that matched the criteria.

All eight have the subject to the left of the adverb/negation:[CP Object C+I+V [IP Subject [VP neg/adv tSubj tV] tI ]]

Slide24

Kid structuresHypothesis: Kids have full knowledge

of the principles and processes and constraints of grammar. Their representations can be basically adult-like.

But kids seem to optionally allow infinitives as matrix verbs (which they grow out of).

(And when they use an infinitive, it acts like an infinitive.)

What’s happening when kids use an infinitive?

Slide25

Harris & Wexler (1996)Child English bare stems as “OIs”?

In the present, only morphology is 3sg

-

s

.

Bare stem isn’t unambiguously an infinitive form.

No word order correlate to finiteness.

OIs are clearer in better inflected languages. Does English do this too? Or is it different?

Hypotheses:

Kids don’t “get” inflection yet;

go

and goes are basically homonyms.These are OIs, the -s is correlated with something systematic about the child syntax.

Slide26

Harris & Wexler (1996)Hypothesis:

RIs occur when T is missing from the structure (the rest being intact).

Experiment:

Explore something that should be a consequence of having T in the structure:

do

support.

Rationale:

Main verbs do not move in English.

Without a modal or auxiliary, T is stranded:

The verb -ed not move.

Do

is inserted to save T.Predicts: No T, no do insertion.

Slide27

Harris & Wexler (1996)Empirically, we expect:

She go

She goes

She not go

(no T, no

do

)

She doesn’t go

(adult, T and

do

)

but neverShe not goes (evidence of T, yet no do).Note: All should be options if kids don’t “get” inflection.

Slide28

Harris & Wexler (1996)Looked at 10 kids from 1;6 to 4;1

Adam, Eve, Sara (Brown), Nina (Suppes), Abe (Kuczaj), Naomi (Sachs), Shem (Clark), April (Higginson), Nathaniel (Snow).

Counted sentences…

with

no

or

not

before the verb

without a modal auxiliary

with unambiguous 3sg subjects

with either

-s or -ed as inflected.

Slide29

Harris & Wexler (1996)

Affirmative:

43% inflected

Negative:

< 10% inflected

It not works Mom

no N. has a microphone

no goes in there

but the horse not stand ups

no goes here!

aff

neg

-inflec

782

47

+inflec

594

5

Slide30

Harris & Wexler (1996)

Small numbers, but in the right direction.

Generalization:

Considering cases with no auxiliary, kids inflect about half the time normally, but almost never (up to performance errors) inflect in the negative.

If presence vs. absence of T is basically independent of whether the sentence is negative, we expect to find

do

in negatives about as often as we see inflection in affirmatives.

Also, basically true: 37% vs. 34% in the pre-2;6 group, 73% vs. 61% in the post-2;6 group.

Slide31

Harris & Wexler (1996)

When kids inflect for tense, do they inflect for the tense they mean?

(Note: a nontrivial margin of error…)

Inflected verbs overwhelmingly in the right context.

present

past

future

bare stem

771

128

39

-s

418

14

5

-ed

10

168

0

Slide32

Harris & Wexler (1996)

Last, an elicitation experiment contrasting affirmative,

never

(no T dependence for adults), and

not

.

Does the cow always go in the barn, or

does she never go

?

Does the cow go in the barn or

does she not go

in the barn?Do you think he always goes or do you think he never goes?Do you think that he goes, or don’t you think that he goes?Processing load? Extra load of not alleviated by leaving off the -s? If that’s the case, we’d expect never and not to behave the same way—in fact, never might be harder, just because it’s longer (and trigger more -s drops).

Slide33

Harris & Wexler (1996)Affirmatives inflected often,

not

inflected rarely,

never

sort of inbetween.

Looking at the results in terms of whether the question was inflected:

Kids overall tended to use inflection when there was inflection in the question.

When the stimulus contained an

-

s

:

affirmative: 15 vs. 7 (68% had an -s)never: 14 vs. 16 (48%)not: 4 vs. 12 (25%) —quite a bit lower.

Slide34

An alternative to missing TMuch of what we’ve seen so far could also be explained if kids sometimes use a

null modal

element:

Idea: I want to eat pizza. I will eat pizza.

RI? I

want

to eat pizza. I

will

eat pizza.

First question:

why

modals?Second, they don’t (always) seem to mean what they should if there is a null modal. 20/37 seem to be clearly non-modal (according to P&W93).Thorsten Ball haben (T already has the ball)

Slide35

Modal dropCan we test this another way? What are the properties of adult modals?

Adult modals are in position 2, regardless of what is in position 1. If kids are dropping modals, we should expect a certain proportion of the dropped modals to appear with a non-subject in position 1.

But

none

occur—nonfinite verbs also seem to come with initial

subjects

.

Why? Well, if V2 is a) movement of V to T to C, and b) “topicalization” of something to SpecCP; and, if this is triggered by V reaching C: There’s no need to move anything to SpecCP if V remains unmoved. The subject remains first.

Slide36

Modal dropJust to be sure (since the numbers are small), P&W check to make sure they would have

expected

non-subjects in position 1 with nonfinite verbs if the modal drop hypothesis were true.

17% of the verbs are infinitives

20% of the (finite) time we had non-subject topicalization

So 3% of the time (20% of 17%) we would expect non-subject topicalization in nonfinite contexts.

Of 251 sentences, we would have expected 8.

We saw

none

.

Slide37

Two hypotheses about learning (Wexler 1998)

VEPS

(

very early parameter setting

)

Basic parameters are set correctly at the earliest observable stages

, that is, at least from the time that the child enters the two-word stage around 18 months of age.

VEKI

(

very early knowledge of inflection

)

At the earliest observable stage (two-word stage), the child knows the grammatical and phonological properties of many important inflectional elements of their language.

Slide38

Very Early Parameter SettingAs soon as you can see it, kids have:VO vs. OV order set (Swedish vs. German)

V



I [yes/no] (French vs. English)

V2 [yes/no] (German vs. French/English)

Null subject [yes/no] (Italian vs. Fr./E.)

So,

at least

by the 2-word stage, they have the parameters set (maybe earlier)

Slide39

VEKI?Generally,

when kids use inflection, they use it correctly

. Mismatches are vanishingly rare.

English (Harris & Wexler 1995)

German (Poeppel & Wexler 1993)

Again, this is kind of contrary to what the field had been assuming (which was: kids are slow at, bad at, learning inflection).

Slide40

Ok, but…

So:

Kids have the full functional structure available to them, and they set the parameters right away and know the inflection.

What then do we make of the fact that kids make non-adult utterances in the face of evidence that they aren’t

learning

the parameters?

KW: Certain (very specific, it turns out) properties of the grammar

mature

.

Slide41

Root infinitives vs. timeThe timing on root infinitives is pretty robust, ending around 3 years old.

Slide42

NS/OIBut some languages appear not to undergo the “optional infinitive” stage. How can this be consistent with a maturational view?

OI languages:

Germanic languages studied to date (Danish, Dutch, English, Faroese, Icelandic, Norwegian, Swedish), Irish, Russian, Brazilian Portuguese, Czech

Non-OI languages:

Italian, Spanish, Catalan, Tamil, Polish

Slide43

NS/OIWhat differentiates the OI and non-OI languages?

Agreement? Italian (non-OI) has rich agreement, but so does Icelandic (OI).

Null subjects!

Null Subject/OI Generalization:

Children in a language go through an OI stage iff the language is

not

an INFL-licensed null subject language.

Slide44

NS/OI and Hebrew(Rhee & Wexler 1995)Hebrew is a

NS language

but only

in 1st and 2nd person, non-present tense

. Everywhere else (3rd past, future, present) subjects are obligatory.

Hebrew-learning 2-year-olds showed optional infinitives

except in 1/2-past

, and

allowed

null subjects elsewhere, with infinitives.

Slide45

NS/OI and Hebrew(Rhee & Wexler 1995) % of RIs

all OI kids

1/2 past/fut (NS)

else (non-NS)

null subjects

0.6% (1/171)

25% (85/337)

overt subjects

1.4% (1/72)

0.6% (3/530)

kids up to 1;11

1/2 past/fut (NS)

else (non-NS)

null subjects

0 (of 21)

32% (36/112)

overt subjects

0 (of 6)

0 (of 28)

Slide46

Rizzi and truncated treesRizzi (1993/4): Kids lack the CP=root axiom.

The result (of not having

CP=root

) is that kids are allowed to have

truncated structures

—trees that look like adult trees with the tops chopped off.

Importantly

: The kids don’t just leave stuff out—they just stop the tree “early.” So, if the kid leaves out a functional projection, s/he leaves out all

higher

XPs as well.

Slide47

Truncation: < TP < CPIf kid selects anything lower than TP as the root, the result is a root infinitive

—which can be as big as any kind of XP below TP in the structure.

Note in particular, though, it

can’t

be a CP.

So: we expect that evidence of CP will correlate with finite verbs.

Slide48

Truncation: TP < AgrSPPierce (1989) looking at French observed that there are almost no root infinitives with subject clitics—this is predicted if these clitics are instances of subject agreement in AgrS; if there is no TP, there can be no AgrSP.

Slide49

Truncation: TP <> NegP?

There is some dispute in the syntax literature as to whether the position of NegP (the projection responsible for the negative morpheme) is higher or lower than TP in the tree.

If NegP is higher than TP, we would expect not to find negative root infinitives.

But we

do

find negative RIs—(Pierce 1989): in the acquisition of French, negation follows finite verbs and precedes nonfinite verbs (that is—French kids know the movement properties of finiteness, and thus they have the concept of finiteness).

So, is TP higher than NegP?

Hard to say conclusively from the existing French data because there are

not many

negative root infinitives—but further study

could

lead to a theoretical result of this sort about the adult languages.

Slide50

S O Vfin?

Usually (Poeppel & Wexler 1993) German kids put finite verbs in second position, and leave nonfinite verbs at the end.

Occasionally

one finds a

finite

verb at the end.

Rizzi suggests we could look at this as an instance of a kid choosing AgrSP as root, where CP is necessary to trigger V2.

Slide51

*Truncation?: Where train go?Truncation predicts

: If TP is missing, then CP should be missing.

But Bromberg & Wexler (1995) observe that bare verbs do appear in

wh

-questions in child English.

Wh

-questions implicate CP, bare verbs implicate

something

missing (TP or AgrP). So, truncation can’t be right.

Guasti notes that although the logic here works, English is weird in this respect: pretty much all other languages

do

accord with the prediction.

Slide52

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