if引导的条件状语从句总结+习题.docxVIP

if引导的条件状语从句 ［课本链接］ If you do, you II be sorry. （Unit 5, Sect ion A） ［定义］:if 引导的条件状语从句表示假如从句的动作发生，主句的动作就（不）会发生。 ［句子结构］ if 引导的条件状语从句位置灵活，可直接放在主句后面，也可以放在句首。放在句首时，从句后面 要用逗号和主句隔开。如： I ll go to see you if I have time. 如果有时间，我就去看你。 If it rains tomorrow, we ll sta y at home. 女口果明天下雨，我们就呆在家里。 ［时态呼应］ 在复合句中：⑴ 当主句是一般现在时或是一般将来时时；（2）当主句是祈使句时；（3）当主句含有情 态动词时，if引导的条件状语从句通常用一般现在时。 用法 例句 ① 主句为一般将来时态， if从句用一般 We will stay at home if it rains tomorrow. 现在时态。（主将从现） 如果明天下雨，我将要呆在家。 ② 主句中含有情态动词， if从句用一般现 If you finish your homework, you can go home now. 如果 在时态。（主情从现）如: 你做完了作业，你现在可以回家了。 may/might/can/could/must/should/would ③ 主句为祈使句，if从句用一般现在时态。 Dori t jump into the river if you feel very hot. 如 （主祈从现） 果你感到很热，不要跳入河里。 ④ 主句为一般现在时时态， if从句用一般现 It s dangerous if you play with the knife. 玩儿刀是 在时态。（主现从现） 危险的。 如： If she doesn t come, she will be sorry. 如果她不来，她会遗憾的。 Have a good rest if you are tired. 如果累了，你就好好休息一下。 We must study hard if we want to pass the final exam. 如果想通过期末考试，我们必须努力学 [ 同义句转换 ] 1. 用“祈使句＋ and / or ＋一般将来时的句子”转换。如： If you work hard, you II pass the exameasily. f Work hard, and you II pass the exam easily. 努力学习，你将很容易通过考试。 If you don t hurry up, you II miss the train. f Hurry up, or you II miss the train. 快点儿，否则你就赶不上火车了。 2. 用含介词 with 或 without 的介词短语转换。如： If there is no water, fish can t Iive. f Fish can t Iive without water. 离开水，鱼不能 生存。 【边学边做】 If there no buying and seIIing of animaIs, there no kiIIing in nature. A. is; wiII he B. wiII be; wiII be C. is; is D. wiII be; is The students have a sports meeting this weekend if it . A. wont; rains A. wont; rains B. wiII; rains C. wont; wiII rain D. are going to; is going to rainIf you to the party, you to; is going to rain If you to the party, you A. wiII go B. went C. go D. goingare you going to do tomorrow? --We A. isn t rain B. rain C. won II have a great time. II go to the Iibrary tomorrow if it ___ t rain D. doesn t rain If I eat food, I II be very fat. A. too many B. many too C. too much D. much too I II give the book t