to do →to be done to be doing to have done →to have been done 动词不定式的用法,这几个怎么回事?
问题描述：
to do →to be done to be doing to have done →to have been done 动词不定式的用法,这几个怎么回事?
答
to do不定式的一般式
to be done 一般是的被动
to be doing 一般式的进行时
to have done不定式的完成式
tohave beendone不定式完成式的被动都与什么时态连用？或什么句式下用啊？它不表示 时态，只表示不定式与主句谓语的先后关系。