零条件句

型态

在零条件句中,两个子句都是用一般现在时。

if 子句(条件/情况) 主要子句(结果)
if + 一般现在时 一般现在时
If this thing happens that thing happens.

就如所有条件句,子句的顺序并没有硬性规定。当您要改变子句的顺序时,必须重新安排代词的位置,以及调整标点符号,但意思基本上是一样的。在零条件句中,由于两个子句表达的都是事实,因此把「if」换为「when」并不会改变意思。

举例
  • If you heat ice, it melts.
  • Ice melts if you heat it.
  • When you heat ice, it melts.
  • Ice melts when you heat it.
  • If it rains, the grass gets wet.
  • The grass gets wet if it rains.
  • When it rains, the grass gets wet.
  • The grass gets wet when it rains.

作用

零条件句是用来陈述实际的情况,一般论及真理,好比科学现象。在这些句子中,时间是指现在或任何时候,而情况是实际且可能的

举例
  • If you freeze water, it becomes a solid.
  • Plants die if they don't get enough water.
  • If my husband has a cold, I usually catch it.
  • If public transport is efficient, people stop using their cars.
  • If you mix red and blue, you get purple.

零条件句时常被用在给予指令,在主要子句会用命令/期使句。

举例
  • If Bill phones, tell him to meet me at the cinema.
  • Ask Pete if you're not sure what to do.
  • If you want to come, call me before 5:00.
  • Meet me here if we get separated.