⑤引导条件状语从句。意为“假使、假设”。
Supposing that you were in my position, what would you do?
On condition that you were lost in the desert, you should ask for help as soon as possible.
3. 引导强调句。
It is Mrs. white that makes the decision in her family, not her meek little husband.
It is an ill wind that blows nobody good.
第四、that用作副词。
1. that用作普通副词。
I was that/so angry I could have hit him.
2. that用作关系副词。引导定语从句,可以代替when,where,why或 in which,常可省略。
I will never forget the evening (that) / when we went to the theatre.
The house (that)/where I used to live has been knocked down.