what should i get my sister?

问题描述:

what should i get my sister?
-why don't you get her a camera?
-why not to get her a camera?
-why don't get her a camera?
这三个句子哪个是对的?哪个是错的?为什么?

正确的句子应该是第一个-why don't you get her a camera?这句话是正确的.why not do sth为什么不做……这是一个提建议的方式,是固定搭配.或者是why don't sb do sth为什么(某人)不做……和上面的意思用法是相同的...