Question

unless，as soon as，sothat分别用于引导哪些状语从句

Answer 1

unless “除非”引导条件状语从句，遵循“主将从现原则”可与if 从句互换。

as soon as“一……就……” 引导时间状语从句，遵循“主将从现原则”,如果两个动作发生的时间连续时，前后时态要一致。

so that “以便，为了”引导结果状语从句，前后时态要一致。

如

1. I won't go to his party unless I am invited .

   我不会去（参加）他的聚会除非我被邀请。

＝  I won't go to his party if I am not invited.

   如果我不被邀请，我不会去（参加）他的聚会。

2. I will call you as soon as I get there .

  我一到达那里我就给你打电话。

3. He fell asleep as soon as he lay down.

  他一躺下就睡觉了。

4. Our teacher spoke loudly so that all of us could hear him .

   我们老师大声说以便我们都能听到。