1. Child Syntax and Morphology
Aylin Küntay
Language and Communicative Disorders
Meeting 4

2. Productivity/generativity of language
Syntactic productivity
An infinite number of sentences from a finite list of lexical items (words)
Morphological productivity
“Wug” test (Berko)
Need knowledge of SYNTAX or MORPHOSYNTAX to achieve productivity
Component of grammar governing the ordering of words in sentences

3. Linguistic rules operate over...
Content words (lexical categories) vs. function words (functional categories)
Bound vs. free morpheme
inflectional vs. derivational morphology

4. Overview of grammatical development
Multi word utterances
Morphosyntactic development
in English
MLU
Negation, questions, etc.
Passives
Individual differences

5. Two-word utterances: Telegraphic speech
after a period of one-word utterances, children start putting words together to form the first sentences
underlying relational meanings
show evidence of syntax: the child combines words following certain rules rather than in random fashion
more cereal, *cereal more
with development, more linguistic elements
measuring morphological and syntactic development: MLU (mean length of utterance)
research finds that early word combinations express common semantic relations such as recurrence, disappearance, possession, agent-patient relations

6. Syntax: combinatorial language
MLU: used as an indicator of early syntactic development
observed in 100 spontaneous speech utterances
length is determined by the number of meaningful units, or morphemes
include both content words such as dog, and function words such as the
the addition of each new morpheme reflects the acquisition of new linguistic knowledge
better indicator of the level of linguistic development than age, although positively correlated
a lot of individual variation among children of the same age
remains useful up to MLU = 4
IPSyn (Index of Productive Syntax): gives credit for a variety of structures in NPs, VPs, questions, negation forms, and sentence structure
good correlation with MLU

7. Issues about using MLU
imitation vs. spontaneous utterances: should we include imitated utterances in our calculations?
highly inflected and synthetic languages such as German, Russian, and Turkish
difficult to figure out what functions as a morpheme in the child’s system
it is easy to obtain inflated numbers
in some languages, calculating the length of utterances in words has proven useful

8. Acquisition of morphology
Brown: the 14 morphemes observed in 3 American children
common order of acquisition: 1. present progressive, 2-3. prepositions in and on, 4. plural, 5. irregular past tense, 6. possessive, 7. uncontractibe copula, 8. articles, 9. regular past tense, 10. regular third-person present tense, 11. irregular third-person present tense , 12. uncontractible auxiliary, 13. contractible copula, 14. contractible auxiliary
de Villiers & de Villiers: found the same order of development in a larger sample of 21 children

9. Reasons for this order
frequency hypothesis: found no correlation between frequency in input and order of acquisition
articles are very common in parents’ speech, but not in children’s
linguistic complexity
semantic complexity: the complexity of meanings encoded in the morpheme
plural encodes number, 3rd person singular encodes number and tense
syntactic complexity: the complexity of rules required for the morpheme

10. Productivity in morphology
Overregularization errors
use the plural morpheme on irregular nouns such as mans, mouses
use the past tense morpheme on irregular verbs such as broked, falled, goed
evidence of the productivity of the child’s morphology
the Wug test (Berko)
an elicited production task in which children were shown novel creatures and actions that were given invented names

11. Morphological Rules Berko (the Wug test)
How do children know the pluralization rule?
This is a Wug
Now there is another one.
There are two of them.
These are two …?

12. Morphological Rules This is a Wug Now there is another one.
Berko (the Wug test)
Do children know the English plural rule with segments (non-words) that they have never encountered before?
Children do not memorize each plural but they have internalized a rule for it
This is a Wug
Now there is another one.
There are two of them.
These are two …?

13. Late developments: Passives
reverses the order of agents and objects
can reveal info about children’s sensitivity to word order rules
very rare in children’s transcripts
full passives produced far less frequently than truncated passives such as in the window was broken
Borer and Wexler: early appearing passives are really adjectival in form, whereas the later-appearing passives are complete verbal passives

14. Individual differences
Holistic vs. analytical strategies
Most children use both

15. Comprehension studies
Before production? Sometimes, often...
Response stragies
No use of syntactic knowledge
Evidence
Preferential looking studies (see the next 2 slides)
Word order
Picture recognition stories with children not yet producing function words
Find the dog for me vs. find was dog for me
But even 5-year-olds have difficulties with sentences such as John promised Bill to go (long distance co-reference relations) (Carol Chomsky, 1969)
indicating they use non-syntactic cues...
But maybe they fail because of performance limitations although they have the adult-like grammar
Syntactic competence vs. performance