考點三十八 時間狀語從句
1. 引導時間狀語從句的連詞
2. when，while，as引導時間狀語從句的區別
when，while，as顯然都可以引導時間狀語從句，但用法區別非常大。
① when可以和延續性動詞連用，也可以和短暫性動詞連用；而while和as只能和延續性動詞連用。
Why do you want a new job when you』ve got such a good one already?
你已經找到如此好的工作，為何還想再找新的？ （get為短暫性動詞）
Sorry, I was out when you called me.
對不起，你打電話時我剛好外出了。 （call為短暫性動詞）
Strike while the iron is hot.
趁熱打鐵。 （is為延續性動詞，表示一種持續的狀態）
The students took notes as they listened.
學生們邊聽課邊做筆記。 （listen為延續性動詞）
② when從句的謂語動詞可以在主句謂語動作之前、之後或同時發生；while和as從句的謂語動作必須是和主句謂語動作同時發生。
a. 從句動作在主句動作前發生，只用 when。
When he had finished his homework, he took a short rest. （finished先發生）
當他完成作業後，他休息了一會兒。
When I got to the airport, the guests had left. （got to後發生）
當我趕到飛機場時，客人們已經離開了。
b. 從句動作和主句動作同時發生，且從句動作為延續性動詞時，when，while，as都可使用。
①When / While / As we were dancing, a stranger came in. （dance為延續性動詞）當我們跳舞時，一位陌生人走了進來。
②When / While / As she was making a phonecall, I was writing a letter. （make為延續性動詞）當她在打電話時，我正在寫信。
c. 當主句、從句動作同時進行，從句動作的時間概念淡化，而主要表示主句動作發生的背景或條件時，只能用 as。這時，as常表示＂隨著……＂ ＂一邊……，一邊……＂之意。
As the time went on, the weather got worse. 隨著時間的過去，天氣變得更糟糕了。The atmosphere gets thinner and thinner as the height increases.
隨著高度的增加，大氣越來越稀薄。
As years go by, China is getting stronger and richer.
隨著時間一年一年過去，中國變得越來越富強了。
The little girls sang as they went. 小姑娘們一邊走，一邊唱。
The sad mother sat on the roadside, shouting as she was crying.
傷心的媽媽坐在路邊，邊哭邊叫。
d. 在將來時的從句中，常用when，且從句要用一般時代替將來時。
You shall borrow the book when I have finished reading it.
在我讀完這本書後，你可以借閱。
When the manager comes here for a visit next week, I』ll talk with him about this.
下周，經理來這參觀時，我會和他談談此事。
③ when用於表示＂一……就……＂的句型中（指過去的事情）。
sb. had hardly（＝scarcely）done sth. when. . . ＝Hardly / Scarcely had sb. done sth. when...
I had hardly / scarcely closed my eyes when someone knocked at the door.
＝Hardly / Scarcely had I closed my eyes when someone knocked at the door.
我剛一閉上眼，就有人在敲門了。
I had hardly / scarcely entered my room when the telephone rang.
＝Hardly / Scarcely had I entered my room when the telephone rang.
我剛一走進房門，電話就響了。
3. 比較until和till
此兩個連詞意義相同。肯定形式表示的意思是＂做某事直至某時＂，動詞必須是延續性的。否定形式表達的意思是＂直至某時才做某事＂。動詞為延續性或非延續性都可以。正確使用這兩個連詞的關鍵之一就在於判斷句中的動詞該用肯定式還是否定式。
肯定句：I slept until midnight. 我一直睡到半夜時醒了。
Wait till I call you. 等著我叫你。
（在肯定句中可用before代替。例如：Let’s get in the wheat before the sun sets.）
否定句：She didn’t arrive until 6 o』clock. 她直到6點才到。
Don’t get off the bus until it has stopped. 公共汽車停穩後再下車。
I didn’t manage to do it until you had explained how. 直到你教我後，我才會做。
區別：
（1）until可用於句首，而till通常不用於句首。
Until you told me, I had heard nothing of what happened.
直到你告訴我以前，出了什麼事我一點也不知道。
（2）until when 疑問句中，until要放在句首。
—Until when are you staying?
—Until next Monday.
注意：否定句可用另外兩種句式表示。
（3）Not until...在句首，主句用倒裝。
Not until the early years of the 19th century did man know what heat is.
直到19 世紀初，人類才知道熱為何物。
Not until I began to work did I realize how much time I had wasted.
直到工作，才認識到我已蹉跎了許多歲月。
（4）It is not until... that...
It was not until I began to work that I realized how much time I had wasted.
（5）表示＂一……就……＂的結構
hardly/scarcely... when/before, no sooner... than 和as soon as都可以表示＂一……就……＂的意思。
I had hardly / scarcely got home when it began to rain. 剛回家，就下起雨來了。
I had no sooner got home than it began to rain.
As soon as I got home, it began to rain.
注意：如果hardly, scarcely 或no sooner置於句首，句子必須用倒裝結構。
Hardly / Scarcely had I got home when it began to rain.
No sooner had I got home than it began to rain.
在下列各句的空格中填入適當的連詞
1. ____________ he comes tomorrow, I shall ask where he has been.
2. ____________ he was speaking, everybody listened carefully.
3. I saw her just ____________ she was getting off the train.
4. Have a good look at that man ____________ you pass him.
5. It was already eight o』clock ____________ we got there.
6. I was about to go out ____________ a visitor came.
7. We』ll go to the country at the beginning of June, ____________ the summer harvest will start.
8. He learned to speak German ____________ he was in Berlin.
9. Henry is in charge of the office ____________ Mr. Smith is away.
10. I listen to the recorder ____________ I have time.
11. He had learned Chinese ____________ he came to China.
12. ____________ the work was done, we sat down to sum up experience.
13. I haven’t seen him ____________ he moved to the other side of the town.
14. I waited ____________ he came back.
15. It was not ____________ he took off his eyeglasses that I recognized him.
16. She likes everything to be in place ____________ she starts to work.
17. The thieves ran away ____________ they caught sight of the police.
18. They decided to go back home ____________ their money ran out.
19. We played outside till sunset, ____________ it began to rain.
20. ____________ I get to the airport, I will phone you to pick me up.
21. They were about to leave ____________ it began to rain.
22. He always stay in bed ____________ lunch time.
23. I like playing tennis ____________ my younger sister prefers watching ball games.
24. ____________ I understand your viewpoint, I don’t agree with you.
25. ____________ she grew older, she became more responsible.
1. （2018 安徽中考）Before the sun ____________, we need to get to the top of the mountain.
A. set B. sets C. is setting D. will set
2. （2018 湖北宜昌中考）—It has been much easier for me to go to work ____________ shared bikes appeared.
—But they also caused plenty of problems.
A. since B. before C. unless D. though
3. （2018 成都中考）Yesterday, I ____________ the subway home when I suddenly found I was on the wrong line.
A. took B. was taking C. had taken
4. （2018 天津中考）Tony was drawing a picture ____________ I was doing my homework.
A. if B. because C. while D. until
5. （2018 甘肅蘭州中考）I will call you as soon as he ____________ here.
A. arrive B. will arrive C. arrives D. arrived
6. （2018 黑龍江龍東地區中考）—Do you know when Mrs. White ____________ for dinner this evening?
—No, but I think she when she is free.
A. will come; will come B. will come; comes C. comes; will come
7. （2017﹒黑龍江齊齊哈爾）—I want to know if he ____________ back tomorrow.
—I』ll call you as soon as ____________.
A. will come; will return B. will come; returns C. comes; will return
8. （2017﹒江蘇南通）It is known to all that the day becomes shorter and shorter ____________ winter comes.
A. before B. when C. until D. since
9. （2017﹒吉林）I won’t go home ____________ the rain stops.
A. since B. so C. until
10. （2017﹒福建）The students were singing happily ____________ I passed the school hall.
A. when B. unless C. though
1. （湖南省澧縣2017屆九年級下學期中考最後一次模擬）― Could you tell me when he ____________ back?
— Sure. He will come back as soon as he ____________ the classroom.
A. will come; finishes cleaning
B. comes; will finish cleaning
C. will come; will finish to clean
2. （湖南省澧縣2017屆九年級下學期中考最後一次模擬）I』ll go to visit your uncle as soon as I ____________ Beijing.
A. get to B. will get to C. got to
3. Mr. Liu has taught us English ____________ he came to our school.
A. until B. because C. though D. since
4. （山東省龍口市蘭高鎮蘭高學校2018屆九年級上學期期中）My father was reading a newspaper ____________ my mother was cooking dinner.
A. when B. while C. as soon as D. Until
5. （山東省龍口市蘭高鎮蘭高學校2018屆九年級上學期期中）Many students didn’t realize the importance of study ____________ they left school.
A. when B. until C. as D. after
6. It’s been five years ____________ we met last time.
A. for B. when C. since D. if
7. A good storyteller must be able to hold his listeners』 curiosity(好奇心) ____________ he reaches the end of the story.
A. if B. unless C. after D. until
8. （江蘇省句容市、丹陽市2017屆九年級下學期中考網上閱卷第二次適應性檢測）The TV programme The Readers (朗讀者) was already over ____________ he got back home yesterday.
A. while B. until C. since D. when
9. —What were you doing ____________ the fire happened?
—I was watching TV at home.
A. if B. while C. when D. since
10. ____________ I saw the delivery man（快遞員）cycling towards me, I knew that was my gift.
A. As B. Although C. Before D. While
11. Tom didn’t believe how terrible the earthquake was ____________ he experienced one.
A. if B. because C. until D. since
12. It has been about half a term ____________ Sandy went into junior high school.
A. though B. when C. if D. since
跟蹤訓練
1. When 2. While / When 3. as 4. when/as 5. when
6. when 7. when 8. while 9. while 10. whenever
11. before 12. After 13. since 14. till/until 15. until
16. before 17. as soon as 18. before 19. when 20. As soon as
21. when 22. until 23. while 24. While 25. As
真題再現
1. B【解析】句意：太陽落山之前，我們需要到達山頂。Before 引導的時間狀語從句不能用將來時態，用一般現在時態來代替，主語the sun單三，謂語動詞用單數形式；故選B。學&科網
3. B【解析】句意：昨天，當我突然發現我撥錯電話的時候，我正在乘地鐵回家。這裡是when引導的時間狀語從句，當某個動詞發生的時候，某個動作正在進行，根據題意，故選B。
4. C【解析】句意：Tony 正在畫畫，而我在做作業。本題考查連詞。由前後兩句話的 was doing 能發現是兩個過去進行時的動作，因此可以選用 while 連結，屬於時間狀語從句。與 A. if 引導的條件狀語從句和 B. because 引導的原因狀語從句無關。而 D. until 表示直到，與原句邏輯關係不符。故正確答案為C。
6. A【解析】句意：——你知道懷特太太今晚是否來吃晚飯嗎？——不知道。但我認為她有時間的話她會來。問句為賓語從句，根據this evening今晚，可知句子為一般將來時，構成：will do.回答是when引導的時間狀語從句。從句是一般現在時，主句應用將來時。故答案是A。
7. B 【解析】句意：——我想知道他明天是否回來。——他一回來我就打電話給你。分析句子得知，在I want to know if he _____back tomorrow中，if引導的賓語從句，意思是＂是否＂而不是＂如果＂，時態不遵循主將從現，根據後文tomorrow，故用一般將來時態will come；下文中as soon as 表示一……就，它引導的時間狀語從句，主句是一般將來時，as soon as 引導的條件狀語從句用一般現在時，結合句意和語境可知選B。
8. B 【解析】句意：眾所周知，當冬天到來時，白天變得越來越短。A. before＂在……之前＂；B. when＂當……的時候＂；C. until＂直到……為止＂；D. since＂既然；由於＂。故選B。
9. C 【解析】句意：直到雨停了我才回家。A. since自從，引導時間狀語從句；B. so所以，引導原因狀語從句；C. until直到……才，引導時間狀語從句。根據句意，可排除A和B，故選C。
10. A 【解析】句意：當我經過學校大廳的時候學生們正在歡快地唱著歌。根據題幹前半句The students were singing happily學生們正在歡快地唱著歌，後半句I passed the school hall. 我經過學校大廳可推知句子是一個時間狀語從句，when當……時候；unless除非；though儘管，只有A選項符合題意。故選A。
模擬檢測
1. A 【解析】句意：——你能告訴我他將什麼時候回來嗎？——當然可以。他一打掃完教室就會回來。本題第一句是賓語從句，第二句是時間狀語從句。根據回答He will come back...可知，本題第一空用一般將來時；第二空主句是一般將來時，as soon as引導的時間狀語從句用一般現在時。故選A。
2. A 【解析】句意：我一到北京就去看望你的叔叔。主句是一般將來時，as soon as引導的時間狀語從句用一般現在時。故選A。
4. B 【解析】句意：我的父親正在讀報紙，而我的母親正在做晚飯。when當……時候；while然而，表示兩者進行對比；as soon as一……就……；until直到……。此處是我父親和母親所做的事進行對比，故用連詞while。故選B。
5. B 【解析】句意：許多學生直到離開學校後才認識到學習的重要性。when當……時候；until直到……；as當……時候；after在……之後。not… until…＂直到……才……＂，故選B。
6. C 【解析】句意：自從我們上次見面已經5年了。for因為，為了；when當……時候；since自從；if如果。主句It’s been是It has been的縮寫，是現在完成時態，since是自從的意思，引導時間狀語從句，從句中用一般過去時態，主句用現在完成時，故選C。
7. D 【解析】句意：一個好的講故事的人必須能夠保持聽者的好奇心，直到他到達故事的結尾。if如果，引導條件狀語從句；unless除非，如果不；after在……之後；until 直到……時候。根據句意可知，講故事的人應該保持聽者的好奇心一直到故事講完，故應選D。
8. D 【解析】句意：當他昨天回到家的時候，電視節目《朗讀者》已經結束了。A.當……時候；B.直到……；C.自從；D.當……時候。因為get為瞬間動詞，故選D。
9. C 【解析】句意：——火災發生時你在幹什麼？——我在家看電視。A. if連詞，如果，引導條件狀語從句；B. while連詞，當……時候，引導時間狀語從句，謂語動詞為延續性動詞；C. when連詞，當……時候，引導時間狀語從句，謂語動詞既是延續性動詞也可是短暫性動詞；D. since連詞，自從，引導時間狀語從句。happened暫時性動詞，故選C。
10. A 【解析】句意：當我看到送貨員騎著自行車向我跑來時，我知道那是我的禮物。A. As同時，當……時；B. Although儘管，錶轉折；C. Before在……之前，表時間；D. While與……同時，表時間。本句是時間狀語從句，根據句意，BC兩項與句意不合，可排除。as和while都可接時間狀語從句，表示主句和從句的動作同時進行，但用法有別。如果主句和從句表示的是兩個同時(或幾乎同時)發生的短暫性（非持續性）動作，需用 as / when，而不可用while。結合句意和語境，可知選A。
11. C 【解析】句意：湯姆不相信地震有多麼可怕，直到他經歷了一次地震。A. if連詞，如果，引導條件狀語從句；B. because連詞，因為，引導原因狀語從句；C. until連詞，直到……，引導時間狀語從句，not...until...直到……才……。D. since連詞，自從，引導時間狀語從句。故選C。