Through the compilation and research of the East China Normal University Vocabulary Test, this study explored the development of receptive and expressive language abilities of 58 children in the 2–3-year-old age group and 36 children in the 4–5-year-old age group. Results found that the children’s score of receptive vocabulary is higher than the score of expressive vocabulary, while there is a significant correlation between receptive vocabulary and expressive vocabulary. Moreover, children in the group of 2–3-year-olds had significantly lower scores than children in the group of 4–5-years-olds in both receptive and expressive vocabulary. Further analysis points out the earliest and most common word class of children is nouns, followed by verbs. Among the verbs, active verbs are the first to be acquired. Classifiers are the last acquired vocabulary by Chinese children. The exploration of phonetic errors reflects that children of 2–3 years old tend to misunderstand words by the similar sounds in words, but as their age increases, the number of phonetic errors decreases. Moreover, the results also indicate that biological and specific things are the two semantic categories learned by children. With cognition developing with age, the number of the words in different semantic categories that children acquired expands.
