固定搭配
unless = if...not.
e.g. Let's go out for a walk unless you are too tired.
If you are not too tired, let's go out for a walk.
if 引導的條件句有真實條件句和非真實條件句兩種:
真實條件句,
如:If it rains tomorrow, we won’t go on a picnic.
非真實條件句是虛擬語氣的一種,表示與事實相反,如:
If I were you, I would go with him.
so/as long as只要
由as (so) long as, in case引導。
So long as you’re happy, it doesn’t matter what you do.
只要你高興,你做什麼都沒有關係。
You may borrow my book as long as you keep it clean.
只要你保持書的清潔,你就可以把我的書借去。
Take your umbrella in case it rains.
帶著你的傘吧,以防下雨。
語法
經典語句:If it dosen't rain tomorrow,we will go to the zoo.
If you open the door,I will come in.
條件狀語從句就是用以表示“在某種條件下,會……”
常用if ,in case , on condition等詞來引導
連線詞主要有 if, unless, as/so long as, on condition that,provided,suppose,supposing 等。.
主句用一般將來時,if或unless引導的條件狀語從句用一般現在時。