Chomsky's Language Acquisition Device (LAD) proposes that:

A: Children learn language by imitating adult speech and being reinforced for correct utterances

B: Children are born with an innate, species-specific capacity for language that includes sensitivity to universal grammatical principles

C: Language is acquired through social interaction and is shaped entirely by the child's environment

D: Language development parallels general cognitive development and depends on sensorimotor achievements

Correct: Children are born with an innate, species-specific capacity for language that includes sensitivity to universal grammatical principles

Chomsky's nativist account holds that the speed and universality of language acquisition — despite impoverished input (the "poverty of the stimulus" argument) — cannot be explained by learning alone. The LAD is a hypothetical innate mechanism providing children with knowledge of Universal Grammar — the set of structural constraints common to all human languages. This enables children to generate and understand novel sentences they have never heard. Chomsky's framework challenged Skinner's behaviourist account of language.

The critical period hypothesis for language acquisition suggests that there is a biologically determined window during which first language acquisition is optimal, and after which it becomes significantly more difficult.

Answer: True

Lenneberg (1967) proposed a critical period for language acquisition ending around puberty. Evidence comes from: (1) Genie — a child deprived of language until age 13 who never achieved full grammatical competence despite intense teaching; (2) studies of deaf children who acquire sign language — those exposed earlier develop superior grammar; (3) second language acquisition — earlier learners consistently achieve higher proficiency and native-like accents than late learners.

What is telegraphic speech, and at what approximate age does it typically appear?

A: Single-word utterances naming objects — appears around 10–12 months

B: Two- to three-word phrases containing content words but omitting function words and inflections — appears around 18–24 months

C: Babbling patterns that mimic the prosody of the native language — appears around 6 months

D: Full sentences with complex grammar — appears around 36 months

Correct: Two- to three-word phrases containing content words but omitting function words and inflections — appears around 18–24 months

Telegraphic speech (Brown, 1973) consists of two- to three-word utterances dominated by content words (nouns, verbs) while omitting grammatical function words and inflectional morphemes — similar to a telegram. Examples: "More milk", "Daddy go", "Big dog". This stage typically emerges around 18–24 months and marks the beginning of syntactic development. Brown's mean length of utterance (MLU) measure is a standard index of grammatical development.

Match each language acquisition milestone to its typical age range.

The social-interactionist theory of language acquisition emphasises:

A: That innate grammatical knowledge is sufficient for language acquisition

B: That language acquisition depends on joint attention, infant-directed speech, and social interaction with caregivers

C: That language is acquired through operant conditioning and reinforcement

D: That all children acquire language in the same way regardless of social input

Correct: That language acquisition depends on joint attention, infant-directed speech, and social interaction with caregivers

Social-interactionist theorists (Bruner, Tomasello) argue that language acquisition depends critically on the quality of social interaction. Key mechanisms include: (1) joint attention — infant and caregiver attending to the same object simultaneously; (2) infant-directed speech ("motherese") — simplified, high-pitched speech that caregiver use; (3) turn-taking routines; and (4) the child's unique human ability to understand communicative intent. Tomasello's usage-based account emphasises that grammar is abstracted from patterns in social communication rather than from innate principles.

Overextension errors (e.g., calling all men "daddy") are evidence that children are actively constructing categories based on shared features, rather than simply imitating adult speech.

Answer: True

Overextension — using a word beyond its conventional meaning (e.g., calling all round objects "ball", all men "daddy") — is a ubiquitous error in early word learning. It demonstrates that children form generalisations based on perceived similarities in shape, movement, or function, rather than passively copying adult labels. Underextension (using a word too narrowly) also occurs. Both error types provide insight into how children construct semantic categories — consistent with constructivist and prototype-based theories of concept formation.