在英语四六级的额备考中，很多同学都沉迷在词汇书海里，而往往忽略了语法。然而语法在四六级的考试中占据重要的地位。比如说翻译和作文，通通离不开语法。还有阅读理解，心中有语法，才能更好的理解文章大意。出国留学网小编特此为大家收集整理了一些四六级考试中的核心语法，以下是详细内容，和小编一起来看一下吧!
虚拟语气：与事实相反的
一、主语从句：
1、it is +adj\ that + 虚拟
2、it is +done(表示建议、要求)that + 虚拟
二、宾语从句：
1、I suggest(表示命令;建议;请求) that shoule +do (在虚拟语气中，shoule have done = ought to have done,其他时候should 不等于ought to) 2、I wish that (用虚拟语气)
三、目的状语：
Lest或者for fear that + (虚拟语气)should do
四、 if从句： 即 主句, if 从句
1、倒装代替if从句：Had\\Were\\Should ，主句
2、but for = without(如果不是)代替if从句， 两个都是介词 But for \\without + 名词 ，主句
3、with + 名词 ，主句
4、if only + (if 从句) 要是该多好
五、隐藏虚拟语气：本打算做但结果没有做的
1、had hoped\\intended\\planned\\expected\\wanted\\meant to do
2、hoped to have done
3、be(was\\were) + to have done 4、would\\should like to have done Would have done 表意愿、将来
Should have done 竟然做了、本应该做的 Could have done 有能力做 Might have done 表示猜测
Need have done 本来需要做的却没有做
主从句时间不一致情况下的虚拟语气
有时条件从句中的动作和结果与主句中的动作，发生的时间不一致，这时动作的形式应根据它所表示的时间加以调整。如：
1. 从句表示将来，主句表示过去：
⑴、If I were not to make a preparation for my experiment this afternoon, I would have gone to see the film with you last night.
2. 从句表示过去，主句表示将来：
⑴、If they had started the early morning yesterday, they would be here now.
⑵、If we hadn' t made adequate preparations, we shouldn' t dare to do the experiment next week。
3.从句表示将来，主句表示现在：
⑴、If we shouldn't have an exam this afternoon, I would go shopping now.
4.从句表示过去，主句表示现在。
⑴、If they had stared the early morning yesterday, they would be here now.
⑵、If you had followed my advice, you would be able to finish the work now.
5.从句表示过去，主句表示过去和现在
⑴、If you hadn’t lent me some money, I couldn’t have bought the new house and most likely I would be still living in the dangerous house now.
在不少情况下，虚拟式已变成习惯说法，很难找出其暗含的条件。
(1) 、You wouldn’t know. 你不会知道。
(2) 、 would like to come. 我愿意来。
(3) 、I wouldn’t have dreamed of it. 这是我做梦也不会想到的。
(4) 、He told the story in such minute detail that he might himself have been an eye-witness. 他将那事讲的非常仔细，简直就象他亲眼看见一样。
6.从句表示现在，主句表示过去
⑴、If I were you, I would have gone to her birthday party.如果我是你，我就去参加她的生日晚会了。(从句说明现在，主句说明过去。)
希望以上内容能对大家有所帮助!出国留学网小编预祝大家能够取得理想的成绩!更多信息敬请关注出国留学网!
推荐阅读：