had been doing 和had been done有什么差别
问题描述:
had been doing 和had been done有什么差别
答
1、首先要区分has been done与 had been done的区别:have/has been done 是现在完成时的被动语态.表示某事被做,.如:The problems have been solved.这些问题已经被解决了.had been done 则是过去的过去,是过去完成...