IF引导的真实条件句(3页).doc

-IF引导的真实条件句-第 3 页真实条件句中if 条件句的时态搭配真实条件句真实条件句用于陈述语气，假设的情况可能发生，其中 if 是如果的意思。时态关系句型： 条件从句 主句一般现在时shall/will + 动词原形If he comes, he will bring his violin.例题：The volleyball match will be put off if it _.A.will rain B. rains C. rained D. is rained答案B。真实条件句主句为将来时，从句用一般现在时。真实条件句用于陈述语气，假设的情况可能发生，其中 if 是如果的意思。注意：1) 在真实条件句中，主句不能用be going to表示将来，该用shall, will.(错) If you leave now, you are never going to regret it.(对) If you leave now, you will never regret it.2) 表示真理时，主句谓语动词便不用shall (will) +动词原形，而直接用一般现在时的动词形式。1.if从句用一般现在时,主句用一般将来时 If he runs hell get there in time.如果他用跑的,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.2.if从句用一般现在时,主句用may/might/can：If 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.3.从句一般现在时,主句用must/should：If you want to lose weight you must/should eat less bread.如果想减肥,你须少吃面包.4.if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.5从句现在进行时,主句一般将来时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.6.从句现在完成时,主句一般将来时If you have finished dinner Ill ask the waiter for the bill.你若吃完,我就叫服务生来算账7.从句用一般将来时,主句用一般将来时：这种结构表示礼貌,意愿和执意坚持.礼貌：If you will/would wait a moment Ill see if Mr.Jones is free.请您稍候片刻,我看看琼斯先生是否有空.意愿：If hell listen to me Ill be able to help him.如果他愿意听我的话,我就会帮助他.执意坚持：If you will play the drums all night no matter the neighbors will complain.你若执意整夜敲鼓,那就难怪邻居抱怨.