ABSTRACT
Children make plenty of noise before they start speaking. They cry, burp, and scream; over the next few months they start cooing, and from four months or so they start laughing. After six months or so they start making the speech-like sounds known as babbling, marked by syllables (consonants and vowels, such as “ba” and “da”), often repeated several times. Around nine months infants show extensive signs of comprehension – they start noticing that certain sounds occur regularly in certain situations – although they might well comprehend a few words a bit earlier. A little later, they start producing their first recognisable words. At about 18 months there is a dramatic increase in the number of words the child knows – this phase has been given the name “the vocabulary explosion”. About the same time children start combining words in their productions. At first they produce two-word utterances, but they soon start producing longer ones. These early longer utterances are appreciably grammatically different from the corresponding adult version, often lacking the grammatical detail, and are usually called telegraphic speech, to emphasise their clipped, abbreviated nature (e.g. “more car”, “bye-bye car”). As the child grows, they acquire the finer syntactic detail, while all the time their vocabulary is increasing quite dramatically. By two and a half they are starting to speak like little adults. Obviously development continues after this; it takes some time to acquire the finer points of the syntax of the language, with the finer points depending on which language the child is acquiring. Vocabulary acquisition continues throughout life, although the rate of acquisition slows down as we get older. It’s been estimated that the average young teenager is still acquiring 10 new words a day.
