Grammatical Development

Grammatical development describes how children acquire the rules that govern how words are combined into phrases, clauses, and sentences. This includes the acquisition of morphology (word structure — e.g. adding "-ed" for past tense) and syntax (sentence structure — e.g. word order, clause combining). Grammatical development is one of the richest areas for data analysis at A-Level.

---

From One Word to Two Words

As discussed in the lesson on lexical development, children begin with single-word utterances (holophrases) around 12–18 months. The transition to two-word utterances typically occurs around 18–24 months and represents a fundamental milestone: for the first time, children are combining words according to rudimentary grammatical rules.

Two-Word Stage

At the two-word stage, children produce utterances that express basic semantic relationships: