條件狀語從句
連接詞主要有 if, unless, as/so long as, on condition that 等。. if 引導的條件句有真實條件句和非真實條件句兩種。非真實條件句已在虛擬語氣中闡述。 unless = if not. Let's go out for a walk unless you are too tired. If you are not too tied, let's go out for a walk.
典型例題 You will be late ___ you leave immediately. A. unless B. until C. if D. or 答案A。 句意:除非你立即走,否則你就廻遲到的。可轉化爲 If you dong leave immediately, you will be late. B、D句意不對,or表轉折,句子如爲 You leave immediately or you will be late.