1、专题13状语从句的基本用法一、状语从句的连词：1. 时间状语从句的连词when, while, as, once, the time, until, before, after, as soon as, instantly。1) when在用的时候，即可以接段时间，又可以接点时间; 有时候还能用来表示微弱的原因。They stood respectfully when he entered the room.I couldnt very well say no when there was no one else she could ask.They figured why they shou
2、ld labor when there was no payoff.2) While 表示在什么期间，一般连接延续的段时间，这时可以用when去替换。I get the house all shipshape while he is away.While Mary was writing a letter, the children were playing outside.但是它还可以用来表示微弱的让步状语从句，不能用when替换。While I admit that there are problems, I dont agree that they cannot be solved.3)
3、 As可以用来代替when和while,表示当什么的时候，I saw Peter as I was getting off the bus. As time passed, things seemed worse.但是它可以用来去表示方式、原因、让步、对比等，不能用when, while替换。Wed better leave the things as they are until the police arrive.We asked Phillip to come with us, as he knew the road.Try as she might, she couldnt get t
4、he door open. Helen comes to visit us as often as she can.4) Once,表示一旦，Once I get him a job, he will be fine.5)The (next, last, this, that, each, every)time表示什么的时候，可以用来做连词。Why dont you drop in for a drink next time you are over this way? 6) Until和beforeUntil=if something happens until a particular t
5、ime, it continues and then stops at that time.He waited until she had finished speaking. 7). Beforea. Earlier than a particular event or action. Say goodbye before you go.b. So that something does not or cannot happen.Before I could say anything more, Holmes had rushed off towards the station.c. Use
6、d to say something must happen in order for something else to be possible.You have to pass a test before you can get a license.d. Used to warn someone that something bad will happen to them if they dont do something.Get out before I call the police!e. Used to emphasize that someone does not want to
7、do something.She would die before she would admit she was wrong. f. Used to say that something happens after a period of time. It will be a while before we know the results. 2. 条件状语从句的连词If, unless, in case, If I someone dont show you the pass, dont let him in. Dont let someone in unless he shows you
8、 the pass. He have a large sum of money in his pocket in case he might buy some large items. 3. 目的、结果状语从句连词So that, in order thatHe wore a mask so that no one should recognize him.I am saving money in order that I can buy a house.4. 让步状语从句连词Although, though, even if, as, no matter+疑问词=疑问词+ever, whet
9、her。Id like to see you whenever its convenient.I am calling the doctor, whether you like it or not. 5. 原因状语从句连词Since, as, because, forI cannot tell you whether she is old or young, for I have never seen her. 二、状语从的特殊性：在使用状语从句的时候，要注意从句前后时态的一致性。一般情况来讲，从句与主句的时态保持一致。有的时候， 所谓的“一致”不是绝对的，有可能主句是“现在进行时”，而从句用
10、“一般现时”。但是有一种现象我们应该注意，就是遇到某些连词(if, unless, when, until, til, as soon as, the moment, each time, as long as, after, before等)时，主句用“将来时”，从句用“现在时”代指将来，简化“主将从现”。1. Also, sometimes pre-anger does not have to do with a lasting condition, but rather a temporary statebeforea triggering event has occurred.情态动词
11、在含义上即表达将来时，而后面用的是现在完成代指将来。2. And,beforeI finish, let me just give you some advice which should make your stay more enjoyable.祈使句在含义上也表达将来时，所以“let me just give you some advice”是一个将来的概念，从句中用的是一般现在代指将来。3. As recently reported in The Auk: ornithological advances, some mother birds may teach their young
12、to sing evenbeforethey hatch? 情态动词may可以有将来的含义，后面的从句用一般现在时。4. Beforechoices are finalised, parents will be asked to.本句中所用的是典型的“主将从现。”相应练习：1. Ifeveryone is giving you the same answer, you _(not be)able to use it.2. IfI have the chance to attend the class, I_ (go) to cut out a bird.3. Unlessshe reached
13、 the station before the express did, many, many lives _(be)lost.4. Everyone enjoys the life-saving benefits vaccines provide, but they _ (exist) only aslongas everyone shares in the risks.5. Beforethe tool came out, small farmers _(can not) touch the price per pound offered by California farms.6. As
14、you make reading a regular part of your life, you _ (make) more connections, stay more focused and understand the text better.7. If you _(miss)this chance, it may be yearsbeforeyou get another one.8. It has been really cold lately and the school should consider letting the students in to get warmbef
15、orethe weather _(get)even colder.9. As soon asrelations _(improve)they will be allowed to go.10. Assoonas someone spotted the boat, everyone _(do)last-minute tidying and change into fancy clothes.11. We will give you a call assoonas it _(fix).12. Because of the confusion, Merat thinks some car maker
16、s_(wait)untilvehicles can be fully automated without operation.13. The set _(work)so beautiful when I first got it home that I would keep it onuntilstations signed off for the night.14. Butifthe damage_(cause) by the user, you will have to pay for the repair.15. But the urge _(will)no doubt be great
17、erifyou were living on the streets with little food and money.答案：1. wont be 2. am going 3. would be, 4. will exist 5. couldnt 6. will make 7. miss 8. gets 9.improve 10. would do 11. is fixed 12. will wait 13. worked 14. is caused 15. would三、状语从句的省略：（口诀见非谓语结构解析）状语从句在应用中，经常会出现省略的形式。主要看从句中谓语动词同主语的主被动关系
18、，如果是主动的关系，可以用doing,如果是被动关系，可以用done；如果是主系表结构，可以去掉主系留表语。例如：1. If the monkeys touched the left side of the screen they would be rewarded with seven drops of water or juice. If touching the left side of the screen, the monkeys would be rewarded with seven drops of water or juice.2. When the monkeys adde
19、d two numbers, they always paid attention to the larger of the two, and then added only a fraction（小部分）of the smaller number to it. When adding two numbers, the monkeys always paid attention to the larger of the two, and then added only a fraction of the smaller number to it.以上的省略用法，是英语写作中比较常用的高级句式，
20、我们可以试着将下面的句子变成缩略的形式。对应练习：1. When they were free from work，they invited us to local events and let us know of an interesting competition to watch，together with the story behind it._，they invited us to local events and let us know of an interesting competition to watch，together with the story behind i
21、t.2. Whaley recalls（回想起）how at the beginning of the year, when he was called upon to read, Chris would excuse himself to go to the bathroom. Whaley recalls（回想起）how at the beginning of the year, _, Chris would excuse himself to go to the bathroom.3. As I heard these stories, Im skeptical about the pl
22、ace other destinations are described as “purer” natural experiences._, Im skeptical about the place other destinations are described as “purer” natural experiences.4. If they are armed with this knowledge, theyre able to carry out individually targeted campaigns to cheat people._, theyre able to car
23、ry out individually targeted campaigns to cheat people.5. A college classmate of mine, Tim, was an excellent football player, thoughhe weighed much less than the average player. A college classmate of mine, Tim, was an excellent football player,_.6. Many westerners who come to China cook much less t
24、han in their own countriesoncethey realize how cheap it can be to eat out. _many westerners who tcome to China cook much less than in their own countries.7. One group was asked to seek out an interaction with its waiter; the other, to speak only whenit was necessary. One group was asked to seek out
25、an interaction with its waiter; the other, to speak only_.8. When sheaskedme whether I had returned the books to the library, I admitted that I hadnt._, I admitted that I hadnt.9. It is so cold that you cant go outsideunlessyou are fully covered in thick clothes.It is so cold that you cant go outsid
26、e _.10. Eventhough family members sometimes disagreed with each other, they worked together to make the business successful. _, family members worked together to make the business successful.答案：1. When free from work2. when called upon to read3. Hearing these stories4. Armed with this knowledge5. th
27、ough weighing much less than the average player6. Oncerealizing how cheap it can be to eat out.7. when necessary8. (When) asked whether I had returned the books to the library9.unless fully covered in thick clothes10. Even though disagreeing with each other四、单句填空-填入适当的连词。1. _you hand the keys to you
28、r house over to a complete stranger for care, there are decisions you need to make. 2. I really enjoy listening to music_it helps me relax and takes my mind away from other cares of the day. 3. And_many took dollars, many others pinned their own cash to the board. 4. He is willing to accept the new
29、job,_the pay is higher. 5. _ you have reached a thousand dollars, youll find you probably have the motivation to continue to save even more. 6._a predator can eat several species, it can survive the extinction of one of them. 7. She left_I could even make it to the door to offer my thanks. 8. Accord
30、ing to life in likes,_children grew, they became more anxious to get more public approval.9. A strong link is found between two species_a predator sticks to one prey species. 10._there is a lot of talent on a team, some players may make less effort. 11. Tom is so independent that he never asks his p
31、arents opinion_he wants their support.12. Some social apps were popular among the children_ _they supposedly require users to be at least 13. 13. Conditions were_ bad that it was impossible for him to find the trail again. 14. Next time you take a walk, _it is, take in all the sights, sounds and sen
32、sations. 15. The machine will start running _ the electric current is turned on. 16. It is not surprising that young people are likely to burst out，particularly _there are reasons to do so. 17. Most importantly, it needs to direct light _it is needed. 18. They could help promote other industries_the
33、y lie inside or outside arts. 19. _you move to a new area, you should locate the fire alarm pull stations and the two exits nearest your room. 20._we dont stop climate change, many animals and plants in the world will be gone. 21. _ _ _ one doesnt come to rely on it, wishingfora few good things to h
34、appen never hurts anybody. 22. The doctor shares his phone number with the patients_ _they need medical assistance.23. Nosoonerdid she leave my doorstep _ I had emails from two women whose kids go to my sons nursery and who recognized my face. 24. Put all the books _ they belong. 25. Its difficultie
35、s appear so great that,_hard we work, we fail again and again. 26. He stayed _ the car was parked until the owner returned. 27._youve set your mind on the goal, you must go through with the task. 28. Emma, a female crane, has been in their care_she arrived in 2004. 29. It sounds_everything goes well
36、. 30._she founded her company early on in life, she wasnt driven primarily by profit.答案：1.Before, 2.because,3.while, 4. for/because/since/as, 5.Once, 6.If, 7.before, 8.as, 9.when, 10. When, 11. unless, 12. eventhough/if 13. so, 14. wherever, 15. immediately, 16. when 17. where 18. whether 19. Whenever 20. Until 21. As long as 22. incase 23. than 24. where 25. however 26. where 27. Now that=Since 28. since 29. like 30. Although/Though