The document discusses the key components of language: - Semantics refers to the system of meanings expressed by words and phrases. Learning new words is difficult for children. - Phonology is the system of speech sounds in a language. Children learn the phonemes of their native language. - Morphology studies the smallest units of meaning, like morphemes and affixes, which are critical to vocabulary development. - Syntax involves combining words and morphemes into sentences according to grammatical rules. - Pragmatics governs social uses of language based on context, turn-taking, and shared understanding between speakers.