其他知识点：
1) 常考点有：对a、过去的虚拟语气，b、错综句的考查，c、还有去掉if将助动词had ，情态动词should，be动词提前等
2) 要注意哪些词可以用作虚拟语气 如as if(though)，if only, demand, insist, suggest但要注意suggest 表示“表明”时不用虚拟语气,如 her expression suggest that she made a mistake.
3) 要求，建议，命令等+ (should) do，用虚拟语气demand, insist, require，request, demand, desire, ask(要求),suggest，advise, propose(提议)，urge(催促)，vote(投票)，command(命令), order, recommend，intend, petition(恳请)。
4) It is adj. that… 用虚拟语气 important, illegal, essential，vital，appropriate，unfair，dreadful，strange，surprising，natural，unthinkable
5) It’s (high) time后的定语从句中谓语要用虚拟语气(多用过去虚拟语气)
It’s high time we went.
6) 错综时间条件句：有些条件句主句谓语和从句谓语表示的动作在时间上并不一致。
If the weather had been more favorable, the corps would be growing still better. 考试大
If he had received six more votes, he would be our chairman now.
