英语语法略谈“not”用法种种

　　7. “Why not ...?” is used to make a suggestion:

　　If you’re so unhappy, why not leave?

　　8. “Why not ...?” is used to express agreement:

　　--May I go with you? 我可以和你一起去吗?

　　--Why not? 可以呀。

　　--Let's go out for an Italian tonight.

　　--Yes, why not?

　　9. used to insist on his own opinions or ideas:

　　--Are you really going to sue them? 你真的要控告他们吗?

　　--Yes, why not? 是的，为什么不呢?

　　Note：We must use the infinitive without “to” in the questions beginning with “why not” or “why”. But Why not is used to make a suggestion and why is used to indicate that an action is unnecessary and meaningless.

　　--My girl-friend is in a bad mood. 我女朋友心情不好。

　　--Why not (Why don’t you) give her some flowers? 为什么不送给她一些花呢?

　　Why argue with him? He will never change his mind. 为什么跟他争论?他永远不会改变看法的。

　　根据上述why以及why not的用法，我们有理由可判断本文开头中所提仁爱版八上第三单第三话题中的Section B P73中的Why，应该是Why not。