2.6 Summary of Section 2
Human language is a complex communication system that allows the generation of infinitely many different messages by combining the basic sounds (phonemes) into words, and combining the words into larger units called sentences. The way the sounds combine is governed by phonological rules, and the way the words combine is governed by syntactic rules.
Phonemes can be divided into the vowels, which are made by vibration of the vocal folds, and consonants, which are abrupt sounds made by bringing two surfaces in the vocal tract together. Different phonemes have different acoustic shapes, but in connected speech these are variable because of the influence of the sounds before and after (co-articulation), so the hearer has to make a best guess using information from the context.
The meaning of a sentence is more complex than just the sum of the meanings of the words in the sentence. The hearer must also perform a syntactic analysis of the sentence to establish which meanings relate to which others, and to fill in elements that are ambiguous. The syntactic relationships within a sentence are not simply reflected by the order in which the words arrive, so the hearer has to keep the sentence in a working memory buffer whilst different interpretations are tried out in order to come up with one that is both grammatical and meaningful.