1. whether VS if 的用法
2. tell sb to do sth ask sb not to do sth
3. be + doing 表将来
4. 定语从句： 只用that 的情况
只用who 的情况
只用which的情况
as VS which
the same … as / that…
such… as
as … as
介词+ which/ whom
which 引导一个句子的用法 非限制性定语从句
插入语 I think I believe I guess I thought
间隔式定语从句
Is this car the one he bought last year?
Is this the car he bought last year?
What 的用法
5. will be done
be about to be done
be to be done
be going to be done
6. has/ have been done
7. be being done 加always 表示一种厌烦等语气
8. 强调句 it is + 被强调部分 + that 从句
It is not until + 时间 + that 从句
特殊疑问词 + is it that 从句
9. 倒装句 部分否定，含有否定词的 hardly never little only seldom 等， 把情态动词，be 动词， 助动词提到主语 的前面
10. as if ， insist suggest request command ，从句用虚拟语气， 用(should) do 。
