if条件状语从句的时态搭配.doc

注意if 条件句的时态搭配1if从句用一般现在时，主句用一般将来时 If he runs， hell get there in time. 如果他跑，他就会及时赶到那儿。The cat will scratch you if you pull her tail. 如果你拉猫的尾巴，它就会抓你。2if从句用一般现在时，主句用may/might/canIf the fog gets thicker ，the plane may/might be diverted. 如果雾在大一些，飞机可能就会改在别的机场降落。If it stops snowing ，we can go out. 如果雪停了，我们就可以出去。3if从句用一般现在时，主句用must/shouldIf you want to lose weight ，you must/should eat less bread. 如果你想减肥，你必须少吃面包。4if从句用一般现在时，主句用一般现在时If you heat ice， it turns to water. (也可用will turn)如果把冰加热，它就会化成水。5if从句用现在进行时，主句用一般将来时If you are looking for Peter ，youll find him upstairs. 如果你是在找彼得，上楼就会找到他。6if从句用现在完成时，主句用一般将来时If you have finished dinner ，Ill ask the waiter for the bill. 如果你吃完了，我就叫服务生来算账