If 引导的条件状语从句讲解与练习If引导条件状语从句的条件状语从句最常用的连词是if，常见的if条件状语从句表示在某条件下，某事很可能发生，条件是可能存在的。
如：If you ask him，he will help you．如果你请他帮忙，他会帮你的。
If you fail in the exam，you will let him down．如果你考试不及格，你会让他失望的。
If you have finished the homework，you can go home．如果你作业做完了就可以回家了。
1．if从句用一般现在时，主句用一般将来时If he runs he’ll 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/must/shouldIf it stops snowing we can go out. 如果雪停了，我们就可以出去。
If you want to lose weight you must/should eat less bread.如果你想减肥，你必须少吃面包。
(另外，if从句还表示不可实现的条件或根本不可能存在的条件，也就是一种虚拟的条件或假设。
从句多用一般过去时或过去完成时，表示对现在或过去的一种假设。
如：If I were you，I would invite him to the party．如果我是你，我会邀请他参加聚会。
I would have arrived much earlier if I had not been caught in the traffic．要不是交通堵塞，我本会来得早一些。
)If条件状语从句练习( )1. If I find his phone number, I ______ you.A. tellB. toldC. will tellD. have told( )2. I __ the CDs to you if I have time tomorrow.A．will return B. returned C. have returned D. return( )3. The students will go to the Summer Palace if it ________tomorrow.A. won' t rainB. isn' t rainingC. doesn' t rainD. isn' t rain ( )4. I won’t watch the TV play if my father ___ me do my homework.A. letB. will letC. won’t letD. lets( )5. If you ___quiet, I’ll tell you what happened.A. willB. are C are to be D be( )6. If you go to the party, you ___ a good time.A. would haveB. haveC. will haveD. had( )7. Don’t worry. Peter will call you as soon as he _____ London.A. will get toB. gets toC. get toD. got to( ) 8.He doesn’t tell me when he __. I’ll telephone you as soon as he ___.A. will come, comesB. will come, will comeC. comes, will comeD. comes, comes( )9.-- I don’t know if Dr. White ______ to the party next week.–-- I think he will come if he ______ free.A. comes; will comeB. will come; will beC. comes; isD. will come; is( )10. I don’t know if there ____ a sports meeting next month. If they _____ it, I must get ready for it.A. is; will holdB. will be; holdC. will be; will holdD. will have; hold宾语从句练习( ) 1. I don’t know ___________________.A. what does he like bestB. what he like bestC. what he does like bestD. what he likes best ( ) 2. Can you tell me ______________________?A. where she livesB. where does she liveC. she lives whereD. where she live( ) 3. He asked me _______________________________.A. what time is itB. what time it isC. what time was itD. what time it was( ) 4. Do you know _______________________?A. how much did it costB. how much it did costC. how much it costsD. how much does it cost( ) 5. The man asked her _______________________.A. why did she do itB. why she did itC. why she doesD. why does she do it( ) 6. Nobody knows _________________________.A. when will she come backB. when she come backC. when she will come backD. when does she come back ( ) 7. Mum asked _______________________________.A. where he wasB. where was heC. where he isD. where is he( ) 8. Do you know _______________________________?A. what they are looking forB. what are they looking forC, they are looking for what D. what do they look for () 9. The teacher asked ________________________________.A, who can answer this questionB. who could answer the questionC. what question did she askD. she answered this question( ) 10. I asked her ______________________________.A. whether he has been to AustraliaB. whether has he been to AustraliaC. whether he had been to AustraliaD. whether he goes to Australia( ) 11. The teacher told us ________________________________.A. that light traveled faster than soundB. if light traveled faster than sound.C. that light travels faster than soundD. if light travels faster than sound( ) 12. He said that __________________________________.A. he is doing his homeworkB. he does his homeworkC. he was doing his homeworkD. he do his homework( ) 13. I asked him _________________________.A. where did he goB. where he wentC. where does he goD. where he did go( ) 14. --Excuse me, could you tell me _____ get to the plane?--Certainly. Go straight alone here.A. how can weB. how we canC. when can weD. when we can( ) 15. Do you know _____he will ride here at 8 tomorrow morning?A. whenB. whereC. whetherD. how ( ) 16. --Can you tell me why __________________?--Because I want to help the people there.A. do you go to TibetB. did you go to TibetC. are you going to TibetD. you are going to Tibet ( ) 17. Do you know _______________________________?A. what time does the train leaveB. what time leaves the trainC. what time the train leaveD. what time the train leaves( ) 18. Could you tell me _______________________?A. who is heB. where’s the nearest res taurantC. if he will come tomorrowD. which way is to the underground station( ) 19. --Do you know ___________?--Sorry. I don’t know. You may ask the woman over there.A. when the shop opensB. when is the shop openC. when does the shop openD. when will the shop open ( ) 20 --Dad, do you know ____________? --In half an hour.A. when will the football game startB when the football game will startC. when is the football game going to startD. when shall we start the football game。