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He has just arrive but he talks as if he knew all about it.为

来源:学生作业帮 编辑:搜搜做题作业网作业帮 分类:英语作业 时间:2024/06/18 02:01:03
He has just arrive but he talks as if he knew all about it.为什么用knew?
为什么不用know?
是不是只有在主句的谓语动词是实意动词才用虚拟语气?谢谢了两位老师!
He has just arrive but he talks as if he knew all about it.为
if后面带的从句分两种,一种是非真实条件句,从句中作为条件的事情在实际情况是根本不可能发生的,这时候就用虚拟语气,if所带的从句的谓语用一般过去式.比如:If I were you.不过如果作为过去事实的非真实条件从句,谓语就要用过去完成式了.
还有一种是真实条件句,从句的条件是真实存在的,就不用虚拟语气,谓语用一般现在时.