Question

it's important that主语从句通常用should加动词原形对不对

It’s important that the librarian（确认图书按时归还）. 问题
它的答案是1）从句：主语从句it is important that …
2）虚拟语气：此处主语从句应使用should + 动词原形,should可以省略
3）语态：此处“按时归还”应使用被动语态be returned
4）词组：make sure（确认）
但是虚拟语气说should+动词原形,怎么用在后面而不是make sure.就算是用在后面,这make sure 怎么不是第三人称单数啊.

Answer 1

答案应是：It's important that the librarian (should) make sure that the book （should）be returned in time.
1.此句有两个从句,第一个that the librarian (should) make sure,是it is important that...要求的虚拟语气,因此make sure 不用第三人称单数的形式.
2.第二个从句是make sure that.宾语从句,同样这里make sure 也要求虚拟语气,因此后面用 (should) be returned