PDF《Title children in Hong Kong》

4 adjectives, adverbs and closed-class grammatical functors, was roughly similar across the age groups. When considering the word tokens, however, there were significant changes in the proportional distribution of the five word classes between age two and three, with the pattern becoming more stable after age four. Specifically, the proportion of closed-class word tokens increased significantly from 39% to 54% between ages two and three, with the percentage of adverb word tokens dramatically decreased from 19% to 4% during this period. Noun and verb tokens changed only slightly between ages two and four, and adjective tokens remained similar across the ages of two to five. More comprehensive analysis of the lexical diversity of these children can be found in Klee, Stokes, Wong, Fletcher &

Gavin'

s (2004) paper. They concluded that lexical diversity, measured using D, increased with age in general. That is, the older the children, the more different words they used when they conversed with an adult. But D was observed to have reached plateau after the mean age of

54 months. This could have been the result of the fact that in these samples, the same set of toys was used for the entire age range of children which spanned over an age span of four years. Ze, Can &

Kwong (2006) is the other study which reported on language development in Cantonese-speaking children in Hong Kong. They examined the different words observed in the language samples of

492 Cantonese-speaking children between the age of three and five years that were originally collected by Opper (1996). In most of these samples, the children engaged in free play with a toy cook set. The children were divided into three age groups at Developing an Expressive Vocabulary Test

5 one-yearly intervals. It was found that children as young as three years of age were able to use words from various word classes, and the total number of different words produced increased with ages. Across all the three age groups, the eight word classes with the highest word tokens were in the same order. The word class with the highest number of tokens was verbs, followed in order by auxiliary verbs, pronouns, nouns, adverbs, classifiers and adjectives, and the word class with the lowest number of tokens was interjections, which were words used to express a strong emotion, for example oh! . A review of the literature suggests that there is a lack of studies on the acquisition of different vocabulary items in Cantonese-speaking children across the preschool years. The two studies reviewed above, Fletcher et al. (2000) and Ze et al. (2006) provided information on the words spoken by Cantonese-speaking preschoolers during conversations. However, it is suggested that speech therapists may not be able to directly use these findings as a normative reference for differentiating children who have delays in expressive vocabulary development from their normal peers, because of the following two limitations observed in these two studies. First, the word list they reported was derived from language samples of the children in each age group and it remained uncertain the age at which a particular word was acquired by most of the children. Second, the contexts in which the language samples were obtained were rather restricted. Both studies involved the preschoolers in activities with specific themes (e.g. bathing the doll), thus, it was possible that these studies did not capture Developing an Expressive Vocabulary Test

6 the range of words the children were actually able to use in other contexts or activities. Test of Expressive Vocabulary for Cantonese-speaking Preschoolers Since individual variations are evident in the rate of acquisition of vocabulary (Bates, Dale &