强调句
句型It is …… that ……
I want to go to America this summer.
It is America that I want to go to this summer.
倒装句
全部倒装：There be 句型 + n + 介词短语
有……在哪里
现在 There is a book on the table.
部分倒装
相当于把陈述句变成一般疑问句
否定词 位于句首
not、no、never、hardly、little、scarcely、seldom、not until、not only……
I will never do it.
never will I do it.
only 位于句首
虚拟语气（非真实）
1、不是真的。
2、改变时态
3、虚拟条件句、名词性从句中
if虚拟条件句
| if从句 | 主句 | |
|---|---|---|
| 假设过去 | had done | would +have done |
| 假设现在 | did(were) | could、should+do |
| 假设未来 | did(were) were to do should do |
might + do |
If I were to have/had/should have time tomorrow, I would help him.
如果你过去嫁给他，你现在就会是一个加油站服务员的妻子
If you had married him, you would be the wife of a gas station attendant.
省略if的虚拟条件句
if you had joined us, we would have had more fun.
had you joined us, we would have had more fun. (部分倒装)
名词性从句的虚拟语气
表示“建议，要求，命令”v.后的宾语从句虚拟
从句中用（should）+ do
He suggested that the system should be changed.
suggest,advise,propose,recommend,
order,ask,demand,insist,
require,request……
