word做消息信息时可数吗

　　例句：

　　The appropriate word eluded him.

　　他想不起来那个合适的词。

　　What's the meaning of this word?

　　这个单词的`意思是什么？

　　The first word begins with an F.

　　第一个词以F开头。

　　It's not a word in common usage.

　　这不是一个常用词。

　　I didn't believe a word she said.

　　她说的话我一句都不信。