1.has been sent
2.was cut,has been 表示因果关系 对现在的影响
3.be passed ,was read
4.was seen ,running
5.was made,to study
6.happened
7.were not to be done
虚拟语气表示假设
1.has been sent
2.was cut,has been 表示因果关系 对现在的影响
3.be passed ,was read
4.was seen ,running
5.was made,to study
6.happened
7.were not to be done
虚拟语气表示假设