vocabulary即可作可数名词，也可作不可数名词；当其表示词汇量的多少时，为可数名词，例如have a wide vocabulary词汇量大；当其表示某学科所使用的词汇时，为不可数名词，例如The word has become part of advertising vocabulary这个单词已经成了广告用语。

相关例句：

1、His vocabulary was sound and his grammar excellent.

他的词汇丰富，语法也很精通。

2、Love was a word he'd erased from his vocabulary since Susan's going.

自从苏珊离开后，他再也不提“爱情”这个词了。

3、Most people have a smaller vocabulary in speech than in writing.

多数人口语的词汇量比书面语少。

4、An effective way to enlarge your vocabulary is to read newspapers.

扩大词汇量的一个有效办法就是看报纸。

5、We read to improve our vocabularies.

我们阅读以便扩大词汇量。