why you give up 和why do you give up 有什么区别

问题描述:

why you give up 和why do you give up 有什么区别
前者是口语?

why you give up,不是一个完整的句子,缺少助动词do,所以,这个分句一般充当复合句子的宾语成分
例如:I don't understand why you gave(give) up.
why do you give up 则是一个完整的问句,意思是,你为何放弃