Unit 5 Art world 语法Grammar 原因状语从句 练习（含解析）
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班级 姓名 学号 分数
Unit 5 Art world
原因状语从句
（时间：60分钟，满分：100分）
原因状语从句通常由because, since, as引导。
一、 because
1. because引导的从句表示直接原因，语气最强。because引导的原因状语从句常位于主句之后，但也可放在主句之前，并用逗号隔开。
I am tired because I didn’t sleep well last night.
Because I didn’t finish my homework, I was punished.
2.回答由why提出的问题，只能用because而不能用since，as。
—Why is Serina crying —Because her father had an accident.
3.because不能与并列连词so同时在句中使用。
She was late for school because she missed the bus.
= She missed the bus, so she was late for school.
4. because和because of 有明显的区别。because后面要跟从句，而because of 后跟名词、代词或动名词等。
He is late for school because it rains heavily.
= He is late for school because of the heavy rain.
二、 since / as
1．since引导原因状语从句时，表示显然的或已为人所知的理由，常译为“因为”“既然”，语气比because稍弱，多置于句首，较正式。
Since time is up, let’s have a break.
2．as表示附带说明的“双方已知的原因”，含义与since相同，但语气更弱，没有since正式。
As no classmates were there, I got back soon.
单项选择(本大题共50小题，每小题2分，共100分)
1．（24-25九年级上·江苏扬州·阶段练习）________ white represents purity and peace, it is used in many important situations.
A．While B．Whether C．Since D．Though
2．（23-24九年级上·江苏扬州·期中）_______ it rained heavily, Daddy suggested ________ the room quickly.
A．Since; entering B．As; to enter C．As; to enter into D．Since; entering into
3．（23-24九年级上·江苏宿迁·期中）I want to buy something special for my mother, ________ her birthday is coming.
A．so B．although C．because D．but
4．（2024·江苏连云港·中考真题）Our school life is more interesting now _________ we can enjoy ourselves in different clubs.
A．because B．whether C．unless D．although
5．（2024·江苏镇江·二模）More teachers are willing to receive AI training. ________ AI technology in helping with teaching becomes more and more popular.
A．or B．unless C．because D．though
6．（2024·江苏南京·三模）English is my favorite subject ________ it’s very interesting.
A．if B．though C．whether D．as
7．（2024·江苏南通·二模）—It’s said that Beijing Duck is very delicious.
—Well, ________ we are here, why not have a try
A．though B．unless C．since D．before
8．（2024·江苏宿迁·二模）The athlete received a lot of cheers from the audience _________ she won the champion in the final.
A．because B．though C．so that D．even if
9．（2024·江苏宿迁·二模）Life never runs smoothly ________ it is full of ups and downs.
A．though B．since C．while D．unless
10．（2024·江苏镇江·一模）—It is said that the famous snack smelly toufu in Changsha tastes strange!
—________ we have been here, why not give it a try
A．Since B．When C．If D．Though
11．（23-24九年级上·甘肃酒泉·期中）Mr. Black was late for work ________ his car didn’t work on the way, not ________ the bad weather.
A．because, because of B．because of, because
C．because, because D．because of, because of
12．（24-25九年级上·河北张家口·阶段练习）I didn’t go to watch the movie with him ________ I saw it last week.
A．until B．so C．if D．because
13．（23-24九年级上·安徽淮南·期中）—When shall we start, sir
—_________ every one of us is here, let’s start right now.
A．Before B．Until C．Since D．While
14．（24-25九年级上·全国·课前预习）It’s hard for us to say goodbye ________ we have so many happy days to remember.
A．so B．because C．although D．until
15．（24-25九年级上·广东深圳·课后作业）________ there is no bus service there, we have to walk.
A．When B．If C．Since D．So
16．（24-25九年级上·广东深圳·课后作业）Let’s go home, ________ it is late.
A．so B．and C．as D．but
17．（23-24九年级上·天津宁河·期中）She’s my hero __________ she’s one of the best players in the world.
A．because B．so C．or D．because of
18．（23-24九年级上·青海西宁·开学考试）—________ you’re Lisa’s good friend, you should help her.
—OK, Ms. Jones. I’ ll do my best.
A．Before B．Since C．After D．While
19．（24-25九年级上·全国·单元测试）There are a lot of places of interest in Xi’an ________ it has a long history.
A．if B．because C．as soon as D．so that
20．（2024·江苏无锡·一模）The course of life never runs smoothly ________ it is full of ups and downs.
A．since B．though C．while D．unless
21．（2024·河北唐山·一模）We need to take care of the earth ________ it’s the only planet we have for humans to live on.
A．though B．if C．because D．until
22．（2024·甘肃临夏·一模）Sally likes pandas __________ she thinks they are lovely.
A．so B．but C．because D．though
23．（2024·天津南开·一模）People often give me fans as presents __________ they know I like them.
A．because B．while C．so D．before
24．（22-23九年级上·重庆石柱·期末）Quan Hongchan did really well in the competition ________ she practiced day and night.
A．although B．because C．so D．but
25．（22-23九年级上·江苏南通·阶段练习）—It’s said that Beijing Duck is very famous and delicious.
—Well, _______ we’re here, why not go to the restaurant and order some
A．unless B．though C．whenever D．since
26．（23-24九年级上·辽宁大连·期中）Many older buildings in Dalian look beautiful ________ workers make them look as good as new.
A．while B．if C．although D．because
27．（23-24九年级上·甘肃定西·期中）_______ you have seen how it works, why not try it yourself
A．Now that B．So that C．In order to D．No longer
28．（2023·重庆沙坪坝·模拟预测）_________ you are free today, could you help me with housework
A．Since B．Though C．Unless D．Until
29．（2023·重庆铜梁·二模）—Your English has improved so much! How hard-working you are!
—I didn’t believe. I could make it _______ I tried my best.
A．since B．because C．if D．until
30．（2023·内蒙古兴安盟·一模）Our family would like to buy electric cars ________ they produce less air pollution.
A．because B．so C．but D．and
31．（2023·安徽亳州·二模）It’s hard to say goodbye to our middle school ________ we all have many happy days to remember.
A．because B．before C．until D．unless
32．（2023·安徽滁州·一模）Some students are spending more time at school, ________ schools are doing after-hours caretaking services.
A．because B．and C．so D．but
33．（2023·河北唐山·二模）Many people prefer reading paper books ________ they are comfortable to read.
A．and B．but C．because D．so
34．（2023·北京昌平·二模）We were very happy ________ we won the speech competition.
A．because B．but C．or D．so
35．（2023·江苏无锡·一模）The course of life never runs smoothly ________ it is full of ups and downs.
A．though B．since C．while D．unless
36．（2022·吉林长春·一模）There are so many wonderful things that have come into my life ________ I tried my best.
A．if B．though C．because D．until
37．（22-23九年级上·北京东城·期中）—Hi, Mike! Would you like to fly kites with me
—I’d like to go but I can’t, ________ I have to finish my question survey first.
A．because B．until C．so D．while
38．（22-23九年级上·北京西城·期中）The family had to stay at the hotel ________ it was raining hard.
A．although B．because C．until D．unless
39．（22-23九年级上·北京石景山·期中）It might be a boy’s room _________ the clothes look like a boy’s clothes.
A．when B．because C．but D．so
40．（22-23九年级上·安徽合肥·期中）— Tom, why do you look so tired today
— Oh, I didn’t get enough sleep ________ I have worked for 12 hours yesterday.
A．although B．since C．until D．because
41．（21-22九年级上·江苏淮安·期末）—Why do you like listening to music
—________ it makes me feel relaxed.
A．Because of B．Because C．Since D．As
42．（21-22九年级上·江苏镇江·期末）________ we’ve made the promise, let’s try to keep it.
A．Whether B．Since C．Though D．Unless
43．（2021·江苏盐城·一模）________ the COVID-19 is still spreading rapidly, getting a vaccine(疫苗) is quite necessary.
A．Before B．Since C．Although D．unless
44．（2021·江苏无锡·中考真题）________ we’ve made the promise, let’s keep to it and not give up easily.
A．Whether B．Since C．Though D．Unless
45．（20-21九年级上·江苏苏州·期中）Andy, _________ you haven’t finished your homework, we have to play basketball without you.
A．although B．until C．since D．whenever
46．（21-22九年级上·江苏扬州·期末）________ this computer doesn’t work, let’s try another.
A．Since B．Because C．After D．While
47．（22-23九年级上·江苏无锡·阶段练习）—Do you think I should wear an orange shirt today
—Yes. ________ orange can bring you good luck, it is good for your interview.
A．And B．As C．But D．While
48．（2022·江苏淮安·中考真题）We would like to buy electric cars ________ they produce less air pollution.
A．because B．so C．though D．but
49．（2022·江苏无锡·二模）________ your father is well again, you no longer have anything to worry about.
A．Since B．Before C．Although D．While
50．（2024·上海闵行·二模）Elaine was late for the morning meeting ________ she missed the early bus.
A．unless B．though C．because D．until
参考答案：
题号 1 2 3 4 5 6 7 8 9 10
答案 C A C A C D C A B A
题号 11 12 13 14 15 16 17 18 19 20
答案 A D C B C C A B B A
题号 21 22 23 24 25 26 27 28 29 30
答案 C C A B D D A A B A
题号 31 32 33 34 35 36 37 38 39 40
答案 A A C A B C A B B D
题号 41 42 43 44 45 46 47 48 49 50
答案 B B B B C A B A A C
1．C
【详解】句意：因为白色代表纯洁与和平，所以它被用于许多重要场合。
考查连词辨析。While当……时；Whether是否；Since因为；Though虽然。根据“white represents purity and peace, it is used in many important situations.”可知，句子前句是后句的原因，用since引导原因状语从句。故选C。
2．A
【详解】句意：因为雨下得很大，爸爸建议赶快进屋。
考查连词辨析和非谓语动词。Since因为；entering进入，为enter的动名词或现在分词形式，主要用于具体的空间或物体的进入，以及参与某些活动或比赛；As当……时；to enter为动词不定式；to enter into为动词不定式；entering into进入，表示开始从事某事、参与某活动或讨论细节。根据“…it rained heavily, Daddy suggested…the room quickly.”可知，此处指因为雨下得很大，爸爸建议赶快进屋；前半句与后半句为因果关系，第一个空应用Since引导原因状语从句；suggest doing sth.“建议做某事”，动词短语，第二个空表示“进入房间”，应用entering。故选A。
3．C
【详解】句意：我想给我妈妈买一些特别的东西，因为她的生日快到了。
考查连词辨析。so因此；although虽然；because因为；but但是。根据“I want to buy something special for my mother”和“her birthday is coming”可知，前后是因果关系，前果后因，应该用because引导原因状语从句。故选C。
4．A
【详解】句意：我们的学校生活现在更有趣了，因为我们可以在不同的俱乐部玩得很开心。
考查连词辨析。because因为；whether是否；unless除非；although尽管。分析句子可知，学校生活更有趣的原因是可以在不同的俱乐部玩得开心，前后文之间是因果关系，后文表示原因，应用because连接。故选A。
5．C
【详解】句意：更多的老师愿意去接受AI培训，因为AI科技在辅助教学方面变得越来越受欢迎。
考查连词辨析。or或者；unless除非；because因为；though尽管。根据“AI technology...becomes more and more popular.”可知空后的句子表示老师选择AI培训的原因，用because引导原因状语从句，故选C。
6．D
【详解】句意：英语是我最喜欢的科目，因为它非常有趣。
考查连词。if如果；though虽然；whether是否；as因为。横线后解释原因，所以是as。故选D。
7．C
【详解】句意：——据说北京烤鸭很好吃。——好吧，既然我们在这里，为什么不试一试呢？
考查连词辨析。though尽管；unless除非；since既然；before“在……之前”。根据“we are here, why not have a try”可知，既然在北京，就该去试试北京烤鸭，此处应用since引导原因状语从句。故选C。
8．A
【详解】句意：那名运动员收到了来自观众的无数欢呼，因为她在决赛中赢得了冠军。
考查连词辨析。because因为；though尽管；so that以便于；even if即使。分析前后句关系可知“she won the champion in the final”是“The athlete received a lot of cheers from the audience”的原因，因此应用“because”引导原因状语从句。故选A。
9．B
【详解】句意：生活从不是一帆风顺的，因为它充满了起起落落。
考查连词。though虽然；since因为；while然而；unless除非。根据“Life never runs smoothly...it is full of ups and downs.”可知，此处应用since，引导原因状语从句，表示因为生活充满了起伏，所以它从来都不是一帆风顺的。故选B。
10．A
【详解】句意：——据说长沙有名的小吃臭豆腐吃起来怪怪的！——既然我们在这里，为什么不试试呢？
考查连词辨析。Since既然；When当……时；If如果；Though虽然。根据“why not give it a try ”可知，此处是指既然我们在这里，为什么不去试试，用since引导原因状语从句。故选A。
11．A
【详解】句意：布莱克先生上班迟到了因为他的车在路上坏了，不是因为天气不好。
考查连词和介词短语的用法。because用于引导原因状语从句；because of后需接名词或名词短语。空一处“his car didn’t work on the way,”是句子，用because；空二处后是名词短语“the bad weather”，用because of。故选A。
12．D
【详解】句意：我没有和他一起去看电影因为我上周已经看过了。
考查连词词义辨析。until直到……为止；so因此，所以；if如果；because因为。根据“I didn’t go to watch the movie with him”与“I saw it last week”可知，在这个句子中, 前后两句之间存在明确的因果关系。故选D。
13．C
【详解】句意：——我们什么时候出发，先生？——既然大家都来了，我们现在就出发吧。
考查连词辨析。Before在……之前；Until直到；Since由于、既然；While当……时。根据下文“let’s start right now”可知，现在就出发是由于人都到齐了。故选C。
14．B
【详解】句意：我们很难说再见，因为我们有很多快乐的日子要记住。
考查连词辨析。so所以；because因为；although虽然；until直到。后句“we have so many happy days to remember”是前句“It’s hard for us to say goodbye”的原因，用because引导原因状语从句。故选B。
15．C
【详解】句意：因为那里没有公共汽车服务，我们不得不步行。
考查连词辨析。When当……时候；If如果；Since因为；So所以。根据“…there is no bus service there, we have to walk.”可知，此处说的是“因为那里没有公共汽车服务”，应该用since引导原因状语从句。故选C。
16．C
【详解】句意：让我们回家吧，因为时间太晚了。
考查连词辨析。so所以；and并且；as因为；but但是。横线后“it is late”是前文“Let’s go home”的原因，故选C。
17．A
【详解】句意：她是我的英雄，因为她是世界上最好的运动员之一。
考查连词辨析。because因为，后接句子；so所以；or或者；because of因为，后接名词或代词。根据“She’s my hero...she’s one of the best players in the world.”可知，空后表原因，需用because来引导原因状语从句。故选A。
18．B
【详解】句意：——既然你是丽萨的好朋友，你就应该帮她。——好的，琼斯女士，我会尽力的。
考查连词词义辨析。Before……之前；Since既然；After……之后；While在……期间。根据“you’re Lisa’s good friend, you should help her.”可知，前后句为因果关系，Since“既然”符合语境。故选B。
19．B
【详解】句意：西安有很多名胜古迹，因为它有悠久的历史。
考查连词辨析。if如果；because因为；as soon as一……就……；so that以便。分析句子可知，设空处前后为因果关系，用because引导原因状语从句。故选B。
20．A
【详解】句意：人生之路从不一帆风顺，因为它充满了起伏。
考查连词辨析。since因为；though虽然；while然而；unless除非。根据“The course of life never runs smoothly...it is full of ups and downs.”可知，此空是since引导原因状语从句，表示“因为人生充满了起伏，所以人生之路从来都不是一帆风顺的”。故选A。
21．C
【详解】句意：我们需要照顾好地球，因为它是我们唯一可以供人类生活的星球。
考查从属连词辨析。though尽管；if如果；because因为；until直到。前后句表示因果关系，所以用because引导原因状语从句，故选C。
22．C
【详解】句意：萨利喜欢熊猫，因为她认为它们很可爱。
考查连词辨析。so所以；but但是；because因为；though尽管。根据“Sally likes pandas”和“they are lovely”可知，此处表示原因。故选C。
23．A
【详解】句意：人们经常送我扇子作为礼物，因为他们知道我喜欢扇子。
考查从属连词辨析。because因为；while当……时候；so因此；before在……之前。由“People often give me fans as presents…they know I like them”可知，人们送扇子给我是因为我喜欢扇子，应用because引导原因状语从句。故选A。
24．B
【详解】句意：全红禅在比赛中表现得很好，因为她日夜练习。
考查连词。although尽管；because因为；so所以；but但是。前一句表示她在比赛中表现得好，后一句表示她日夜练习，前后表示因果关系，后一句是原因，因此用because引导原因状语从句，故选B。
25．D
【详解】句意：——据说北京烤鸭很有名，很好吃。——好吧，既然我们在这里，为什么不去餐馆点一些呢？
考查连词辨析。unless除非；though尽管；whenever无论何时；since既然。根据“...we’re here, why not go to the restaurant and order some”可知，“我们在这里”是“点餐”的原因，since引导原因状语从句。故选D。
26．D
【详解】句意：大连的许多老建筑看起来很漂亮，因为工人们使它们看起来像新的一样。
考查连词辨析。while当……的时候；if如果；although虽然；because因为。根据“workers make them look as good as new.”可知，这里是由because引导的原因状语从句。故选D。
27．A
【详解】句意：既然您已经了解了它的工作原理，为什么不亲自尝试一下呢？
考查连词。Now that既然，是连词；So that以便于，是连词；In order to为了，是介词短语；No longer不再，是副词短语。此处接从句，用连词，排除CD两项。建议你自己尝试一下，是因为你已经了解了它的工作原理，因此用now that引导原因状语从句，故选A。
28．A
【详解】句意：既然你今天有空，你能帮我做家务吗？
考查从属连词辨析。Since既然；Though尽管；Unless除非；Until直到。根据“you are free today”可知，今天有空，就可以帮忙做家务，此处应用since引导原因状语从句。故选A。
29．B
【详解】句意；——你的英语进步很大！你真努力啊！——我不敢相信。我能成功因为我尽最大努力了。
考查连词辨析。since自从，既然；because因为；if如果；until直到。根据“I could make it … I tried my best”可知，成功是因为尽了最大的努力，空格后表示成功的直接原因，用because引导原因状语从句，故选B。
30．A
【详解】句意：我们家想买电动汽车，因为它们产生的空气污染少。
考查连词辨析。because因为；so所以；but但是；and和。根据“Our family would like to buy electric cars…they produce less air pollution.”可知，后句是前句的原因，因此此处用“because”来连接。故选A。
31．A
【详解】句意：很难和我们的中学说再见，因为我们都有许多记得的快乐日子。
考查连词辨析。because因为；before在……之前；until直到；unless除非。根据“It’s hard to say goodbye to our middle school …we all have many happy days to remember.”可知，因为度过了许多快乐的日子，所以很难和我们的中学说再见，用because引导原因状语从句，故选A。
32．A
【详解】句意：一些学生花更多的时间在学校，因为学校提供课后照顾服务。
考查连词辨析。because因为；and和；so因此；but但是。根据“Some students are spending more time at school”和“schools are doing after-hours caretaking services”可知，一些学生在学校停留的时间更长，是因为学校提供了课后照顾服务；前后句为因果关系，前果后因，应用because连接。故选A。
33．C
【详解】句意：许多人更喜欢读纸质书，因为它们读起来很舒服。
考查连词辨析。and和；but但是；because因为；so因此。“they are comfortable to read”是许多人喜欢读纸质书的原因，前果后因，用because引导原因状语从句。故选C。
34．A
【详解】句意：我们很高兴，因为我们赢得了演讲比赛。
考查连词辨析。because因为；but但是；or或者；so所以。分析“We were very happy...we won the speech competition.”可知，前后两句是因果关系，前果后因，应用because引导原因状语从句。故选A。
35．B
【详解】句意：人生之路从不一帆风顺，因为它充满了起伏。
考查连词。though虽然；since因为；while然而；unless除非。根据“The course of life never runs smoothly...it is full of ups and downs.”可知，此空应是since，引导原因状语从句，表示因为人生充满了起伏，所以人生之路从来都不是一帆风顺的。故选B。
36．C
【详解】句意：因为我尽了最大的努力，我的生活中出现了很多美妙的事情。
考查连词辨析。if如果；though虽然；because因为；until直到。“I tried my best”是“There are so many wonderful things that have come into my life”的原因，用because引导原因状语从句。故选C。
37．A
【详解】句意：——你好，迈克！你愿意和我一起放风筝吗？——我很想去，但是我不能去，因为我必须先完成我的问题调查。
考查连词辨析。because因为；until直到；so因此；while当……时。“I have to finish my question survey first”是“I’d like to go but I can’t”的原因，用because引导原因状语从句。故选A。
38．B
【详解】句意：因为雨下得很大，这家人不得不住在旅馆里。
考查从属连词。although尽管；because因为；until直到；unless除非。根据语境可知，此处存在因果关系，空格后为原因，故应用because引导原因状语从句。故选B。
39．B
【详解】句意：这可能是一个男孩的房间，因为衣服看起来像男孩的衣服。
考查连词辨析。when当……时候；because因为；but但是；so所以。分析题干可知，前后句是因果关系，前果后因，应用because引导原因状语从句，故选B。
40．D
【详解】句意：——汤姆，你今天怎么看起来这么累？——哦，我没睡好，因为我昨天工作了12个小时。
考查连词辨析。although尽管；since自从；until直到；because因为。根据“I didn’t get enough sleep”和“I have worked for 12 hours yesterday.”可知，汤姆睡眠不足，是因为昨天连续工作了12个小时，前后是因果关系，故用because。故选D。
41．B
【详解】句意：——你为什么喜欢听音乐？——因为它让我感到放松。
考查从属连词。Because of因为，后跟短语；Because因为，后跟句子；Since既然；As由于。根据“Why do you like listening to music ”可知，Why提问的特殊疑问句询问原因，需要使用Because回答。故选B。
42．B
【详解】句意：既然我们做了承诺，让我们试着遵守它吧。
考查连词辨析。Whether是否；Since既然；Though虽然；Unless除非。根据“we’ve made the promise, let’s try to keep it.”可知前后是因果关系，用since引导原因状语从句。故选B。
43．B
【详解】句意：由于新型冠状病毒仍在快速传播，接种疫苗是非常必要的。
考查连词辨析。before在……之前；since由于；although尽管；unless除非。根据“ the COVID-19 is still spreading rapidly, getting a vaccine(疫苗) is quite necessary”可知，“新型冠状病毒仍在快速传播”是接种疫苗的原因，用since引导原因状语从句，故选B。
44．B
【详解】句意：既然我们已经许下了诺言，就让我们信守诺言，不要轻易放弃。
考连词。Whether是否；Since既然；Though虽然；Unless除非；根据“we’ve made the promise, let’s keep to it and not give up easily.”可知，此处表达的是因果关系，应用since连接，引导原因状语从句，故选B。
45．C
【详解】句意：安迪，既然你还没有完成作业，我们只好不带你去打篮球了。
考查连词辨析。although虽然，尽管；until直到；since既然；whenever无论何时。“you haven’t finished your homework”是后句“we have to play basketball without you”的原因，所以用since引导原因状语从句，故选C。
46．A
【详解】句意：既然这台电脑不能工作，让我们试另一台吧。
考查从属连词辨析。Since因为，既然；Because因为；After在……之后；While在……期间。根据“this computer doesn’t work”可知，电脑不工作，是很明显的原因，且置于主句之前，因此应用since来引导原因状语从句。故选A。
47．B
【详解】句意：——你认为我今天应该穿一件橙色的衬衫吗？——是的。因为橙色能给你带来好运，它对你的面试很有好处。
考查连词辨析。And和；As由于；But但是；While当……时。根据“orange can bring you good luck, it is good for your interview”可知，前后句是因果关系，用as引导原因状语从句，故选B。
48．A
【详解】句意：我们想买电动汽车，因为它们产生的空气污染更少。
考查连词辨析。because因为；so因此；though尽管；but但是。上文“想买电动汽车”和下文“电动汽车产生较少空气污染”之间是因果关系，前者是结果，后者表原因，故用because连接。故选A。
49．A
【详解】句意：既然你父亲已经康复了，你再也没有什么可担心的了。
考查连词辨析。Since因为，既然；Before在……之前；Although尽管；While当……时。根据“you no longer have anything to worry about”可知，因为父亲已经康复了，所以不需要担心了；故选A。
50．C
【详解】句意：伊莱恩早会迟到了，因为她错过了早班车。
考查从属连词辨析。unless除非；though尽管；because因为；until直到。结合句意可知，前句“Elaine was late for the morning meeting”与后句“she missed the early bus.”表示因果关系，应用because引导原因状语从句。故选C。
Unit 5 Art world
原因状语从句
（时间：60分钟，满分：100分）
原因状语从句通常由because, since, as引导。
一、 because
1. because引导的从句表示直接原因，语气最强。because引导的原因状语从句常位于主句之后，但也可放在主句之前，并用逗号隔开。
I am tired because I didn’t sleep well last night.
Because I didn’t finish my homework, I was punished.
2.回答由why提出的问题，只能用because而不能用since，as。
—Why is Serina crying —Because her father had an accident.
3.because不能与并列连词so同时在句中使用。
She was late for school because she missed the bus.
= She missed the bus, so she was late for school.
4. because和because of 有明显的区别。because后面要跟从句，而because of 后跟名词、代词或动名词等。
He is late for school because it rains heavily.
= He is late for school because of the heavy rain.
二、 since / as
1．since引导原因状语从句时，表示显然的或已为人所知的理由，常译为“因为”“既然”，语气比because稍弱，多置于句首，较正式。
Since time is up, let’s have a break.
2．as表示附带说明的“双方已知的原因”，含义与since相同，但语气更弱，没有since正式。
As no classmates were there, I got back soon.
单项选择(本大题共50小题，每小题2分，共100分)
1．（24-25九年级上·江苏扬州·阶段练习）________ white represents purity and peace, it is used in many important situations.
A．While B．Whether C．Since D．Though
2．（23-24九年级上·江苏扬州·期中）_______ it rained heavily, Daddy suggested ________ the room quickly.
A．Since; entering B．As; to enter C．As; to enter into D．Since; entering into
3．（23-24九年级上·江苏宿迁·期中）I want to buy something special for my mother, ________ her birthday is coming.
A．so B．although C．because D．but
4．（2024·江苏连云港·中考真题）Our school life is more interesting now _________ we can enjoy ourselves in different clubs.
A．because B．whether C．unless D．although
5．（2024·江苏镇江·二模）More teachers are willing to receive AI training. ________ AI technology in helping with teaching becomes more and more popular.
A．or B．unless C．because D．though
6．（2024·江苏南京·三模）English is my favorite subject ________ it’s very interesting.
A．if B．though C．whether D．as
7．（2024·江苏南通·二模）—It’s said that Beijing Duck is very delicious.
—Well, ________ we are here, why not have a try
A．though B．unless C．since D．before
8．（2024·江苏宿迁·二模）The athlete received a lot of cheers from the audience _________ she won the champion in the final.
A．because B．though C．so that D．even if
9．（2024·江苏宿迁·二模）Life never runs smoothly ________ it is full of ups and downs.
A．though B．since C．while D．unless
10．（2024·江苏镇江·一模）—It is said that the famous snack smelly toufu in Changsha tastes strange!
—________ we have been here, why not give it a try
A．Since B．When C．If D．Though
11．（23-24九年级上·甘肃酒泉·期中）Mr. Black was late for work ________ his car didn’t work on the way, not ________ the bad weather.
A．because, because of B．because of, because
C．because, because D．because of, because of
12．（24-25九年级上·河北张家口·阶段练习）I didn’t go to watch the movie with him ________ I saw it last week.
A．until B．so C．if D．because
13．（23-24九年级上·安徽淮南·期中）—When shall we start, sir
—_________ every one of us is here, let’s start right now.
A．Before B．Until C．Since D．While
14．（24-25九年级上·全国·课前预习）It’s hard for us to say goodbye ________ we have so many happy days to remember.
A．so B．because C．although D．until
15．（24-25九年级上·广东深圳·课后作业）________ there is no bus service there, we have to walk.
A．When B．If C．Since D．So
16．（24-25九年级上·广东深圳·课后作业）Let’s go home, ________ it is late.
A．so B．and C．as D．but
17．（23-24九年级上·天津宁河·期中）She’s my hero __________ she’s one of the best players in the world.
A．because B．so C．or D．because of
18．（23-24九年级上·青海西宁·开学考试）—________ you’re Lisa’s good friend, you should help her.
—OK, Ms. Jones. I’ ll do my best.
A．Before B．Since C．After D．While
19．（24-25九年级上·全国·单元测试）There are a lot of places of interest in Xi’an ________ it has a long history.
A．if B．because C．as soon as D．so that
20．（2024·江苏无锡·一模）The course of life never runs smoothly ________ it is full of ups and downs.
A．since B．though C．while D．unless
21．（2024·河北唐山·一模）We need to take care of the earth ________ it’s the only planet we have for humans to live on.
A．though B．if C．because D．until
22．（2024·甘肃临夏·一模）Sally likes pandas __________ she thinks they are lovely.
A．so B．but C．because D．though
23．（2024·天津南开·一模）People often give me fans as presents __________ they know I like them.
A．because B．while C．so D．before
24．（22-23九年级上·重庆石柱·期末）Quan Hongchan did really well in the competition ________ she practiced day and night.
A．although B．because C．so D．but
25．（22-23九年级上·江苏南通·阶段练习）—It’s said that Beijing Duck is very famous and delicious.
—Well, _______ we’re here, why not go to the restaurant and order some
A．unless B．though C．whenever D．since
26．（23-24九年级上·辽宁大连·期中）Many older buildings in Dalian look beautiful ________ workers make them look as good as new.
A．while B．if C．although D．because
27．（23-24九年级上·甘肃定西·期中）_______ you have seen how it works, why not try it yourself
A．Now that B．So that C．In order to D．No longer
28．（2023·重庆沙坪坝·模拟预测）_________ you are free today, could you help me with housework
A．Since B．Though C．Unless D．Until
29．（2023·重庆铜梁·二模）—Your English has improved so much! How hard-working you are!
—I didn’t believe. I could make it _______ I tried my best.
A．since B．because C．if D．until
30．（2023·内蒙古兴安盟·一模）Our family would like to buy electric cars ________ they produce less air pollution.
A．because B．so C．but D．and
31．（2023·安徽亳州·二模）It’s hard to say goodbye to our middle school ________ we all have many happy days to remember.
A．because B．before C．until D．unless
32．（2023·安徽滁州·一模）Some students are spending more time at school, ________ schools are doing after-hours caretaking services.
A．because B．and C．so D．but
33．（2023·河北唐山·二模）Many people prefer reading paper books ________ they are comfortable to read.
A．and B．but C．because D．so
34．（2023·北京昌平·二模）We were very happy ________ we won the speech competition.
A．because B．but C．or D．so
35．（2023·江苏无锡·一模）The course of life never runs smoothly ________ it is full of ups and downs.
A．though B．since C．while D．unless
36．（2022·吉林长春·一模）There are so many wonderful things that have come into my life ________ I tried my best.
A．if B．though C．because D．until
37．（22-23九年级上·北京东城·期中）—Hi, Mike! Would you like to fly kites with me
—I’d like to go but I can’t, ________ I have to finish my question survey first.
A．because B．until C．so D．while
38．（22-23九年级上·北京西城·期中）The family had to stay at the hotel ________ it was raining hard.
A．although B．because C．until D．unless
39．（22-23九年级上·北京石景山·期中）It might be a boy’s room _________ the clothes look like a boy’s clothes.
A．when B．because C．but D．so
40．（22-23九年级上·安徽合肥·期中）— Tom, why do you look so tired today
— Oh, I didn’t get enough sleep ________ I have worked for 12 hours yesterday.
A．although B．since C．until D．because
41．（21-22九年级上·江苏淮安·期末）—Why do you like listening to music
—________ it makes me feel relaxed.
A．Because of B．Because C．Since D．As
42．（21-22九年级上·江苏镇江·期末）________ we’ve made the promise, let’s try to keep it.
A．Whether B．Since C．Though D．Unless
43．（2021·江苏盐城·一模）________ the COVID-19 is still spreading rapidly, getting a vaccine(疫苗) is quite necessary.
A．Before B．Since C．Although D．unless
44．（2021·江苏无锡·中考真题）________ we’ve made the promise, let’s keep to it and not give up easily.
A．Whether B．Since C．Though D．Unless
45．（20-21九年级上·江苏苏州·期中）Andy, _________ you haven’t finished your homework, we have to play basketball without you.
A．although B．until C．since D．whenever
46．（21-22九年级上·江苏扬州·期末）________ this computer doesn’t work, let’s try another.
A．Since B．Because C．After D．While
47．（22-23九年级上·江苏无锡·阶段练习）—Do you think I should wear an orange shirt today
—Yes. ________ orange can bring you good luck, it is good for your interview.
A．And B．As C．But D．While
48．（2022·江苏淮安·中考真题）We would like to buy electric cars ________ they produce less air pollution.
A．because B．so C．though D．but
49．（2022·江苏无锡·二模）________ your father is well again, you no longer have anything to worry about.
A．Since B．Before C．Although D．While
50．（2024·上海闵行·二模）Elaine was late for the morning meeting ________ she missed the early bus.
A．unless B．though C．because D．until
参考答案：
题号 1 2 3 4 5 6 7 8 9 10
答案 C A C A C D C A B A
题号 11 12 13 14 15 16 17 18 19 20
答案 A D C B C C A B B A
题号 21 22 23 24 25 26 27 28 29 30
答案 C C A B D D A A B A
题号 31 32 33 34 35 36 37 38 39 40
答案 A A C A B C A B B D
题号 41 42 43 44 45 46 47 48 49 50
答案 B B B B C A B A A C
1．C
【详解】句意：因为白色代表纯洁与和平，所以它被用于许多重要场合。
考查连词辨析。While当……时；Whether是否；Since因为；Though虽然。根据“white represents purity and peace, it is used in many important situations.”可知，句子前句是后句的原因，用since引导原因状语从句。故选C。
2．A
【详解】句意：因为雨下得很大，爸爸建议赶快进屋。
考查连词辨析和非谓语动词。Since因为；entering进入，为enter的动名词或现在分词形式，主要用于具体的空间或物体的进入，以及参与某些活动或比赛；As当……时；to enter为动词不定式；to enter into为动词不定式；entering into进入，表示开始从事某事、参与某活动或讨论细节。根据“…it rained heavily, Daddy suggested…the room quickly.”可知，此处指因为雨下得很大，爸爸建议赶快进屋；前半句与后半句为因果关系，第一个空应用Since引导原因状语从句；suggest doing sth.“建议做某事”，动词短语，第二个空表示“进入房间”，应用entering。故选A。
3．C
【详解】句意：我想给我妈妈买一些特别的东西，因为她的生日快到了。
考查连词辨析。so因此；although虽然；because因为；but但是。根据“I want to buy something special for my mother”和“her birthday is coming”可知，前后是因果关系，前果后因，应该用because引导原因状语从句。故选C。
4．A
【详解】句意：我们的学校生活现在更有趣了，因为我们可以在不同的俱乐部玩得很开心。
考查连词辨析。because因为；whether是否；unless除非；although尽管。分析句子可知，学校生活更有趣的原因是可以在不同的俱乐部玩得开心，前后文之间是因果关系，后文表示原因，应用because连接。故选A。
5．C
【详解】句意：更多的老师愿意去接受AI培训，因为AI科技在辅助教学方面变得越来越受欢迎。
考查连词辨析。or或者；unless除非；because因为；though尽管。根据“AI technology...becomes more and more popular.”可知空后的句子表示老师选择AI培训的原因，用because引导原因状语从句，故选C。
6．D
【详解】句意：英语是我最喜欢的科目，因为它非常有趣。
考查连词。if如果；though虽然；whether是否；as因为。横线后解释原因，所以是as。故选D。
7．C
【详解】句意：——据说北京烤鸭很好吃。——好吧，既然我们在这里，为什么不试一试呢？
考查连词辨析。though尽管；unless除非；since既然；before“在……之前”。根据“we are here, why not have a try”可知，既然在北京，就该去试试北京烤鸭，此处应用since引导原因状语从句。故选C。
8．A
【详解】句意：那名运动员收到了来自观众的无数欢呼，因为她在决赛中赢得了冠军。
考查连词辨析。because因为；though尽管；so that以便于；even if即使。分析前后句关系可知“she won the champion in the final”是“The athlete received a lot of cheers from the audience”的原因，因此应用“because”引导原因状语从句。故选A。
9．B
【详解】句意：生活从不是一帆风顺的，因为它充满了起起落落。
考查连词。though虽然；since因为；while然而；unless除非。根据“Life never runs smoothly...it is full of ups and downs.”可知，此处应用since，引导原因状语从句，表示因为生活充满了起伏，所以它从来都不是一帆风顺的。故选B。
10．A
【详解】句意：——据说长沙有名的小吃臭豆腐吃起来怪怪的！——既然我们在这里，为什么不试试呢？
考查连词辨析。Since既然；When当……时；If如果；Though虽然。根据“why not give it a try ”可知，此处是指既然我们在这里，为什么不去试试，用since引导原因状语从句。故选A。
11．A
【详解】句意：布莱克先生上班迟到了因为他的车在路上坏了，不是因为天气不好。
考查连词和介词短语的用法。because用于引导原因状语从句；because of后需接名词或名词短语。空一处“his car didn’t work on the way,”是句子，用because；空二处后是名词短语“the bad weather”，用because of。故选A。
12．D
【详解】句意：我没有和他一起去看电影因为我上周已经看过了。
考查连词词义辨析。until直到……为止；so因此，所以；if如果；because因为。根据“I didn’t go to watch the movie with him”与“I saw it last week”可知，在这个句子中, 前后两句之间存在明确的因果关系。故选D。
13．C
【详解】句意：——我们什么时候出发，先生？——既然大家都来了，我们现在就出发吧。
考查连词辨析。Before在……之前；Until直到；Since由于、既然；While当……时。根据下文“let’s start right now”可知，现在就出发是由于人都到齐了。故选C。
14．B
【详解】句意：我们很难说再见，因为我们有很多快乐的日子要记住。
考查连词辨析。so所以；because因为；although虽然；until直到。后句“we have so many happy days to remember”是前句“It’s hard for us to say goodbye”的原因，用because引导原因状语从句。故选B。
15．C
【详解】句意：因为那里没有公共汽车服务，我们不得不步行。
考查连词辨析。When当……时候；If如果；Since因为；So所以。根据“…there is no bus service there, we have to walk.”可知，此处说的是“因为那里没有公共汽车服务”，应该用since引导原因状语从句。故选C。
16．C
【详解】句意：让我们回家吧，因为时间太晚了。
考查连词辨析。so所以；and并且；as因为；but但是。横线后“it is late”是前文“Let’s go home”的原因，故选C。
17．A
【详解】句意：她是我的英雄，因为她是世界上最好的运动员之一。
考查连词辨析。because因为，后接句子；so所以；or或者；because of因为，后接名词或代词。根据“She’s my hero...she’s one of the best players in the world.”可知，空后表原因，需用because来引导原因状语从句。故选A。
18．B
【详解】句意：——既然你是丽萨的好朋友，你就应该帮她。——好的，琼斯女士，我会尽力的。
考查连词词义辨析。Before……之前；Since既然；After……之后；While在……期间。根据“you’re Lisa’s good friend, you should help her.”可知，前后句为因果关系，Since“既然”符合语境。故选B。
19．B
【详解】句意：西安有很多名胜古迹，因为它有悠久的历史。
考查连词辨析。if如果；because因为；as soon as一……就……；so that以便。分析句子可知，设空处前后为因果关系，用because引导原因状语从句。故选B。
20．A
【详解】句意：人生之路从不一帆风顺，因为它充满了起伏。
考查连词辨析。since因为；though虽然；while然而；unless除非。根据“The course of life never runs smoothly...it is full of ups and downs.”可知，此空是since引导原因状语从句，表示“因为人生充满了起伏，所以人生之路从来都不是一帆风顺的”。故选A。
21．C
【详解】句意：我们需要照顾好地球，因为它是我们唯一可以供人类生活的星球。
考查从属连词辨析。though尽管；if如果；because因为；until直到。前后句表示因果关系，所以用because引导原因状语从句，故选C。
22．C
【详解】句意：萨利喜欢熊猫，因为她认为它们很可爱。
考查连词辨析。so所以；but但是；because因为；though尽管。根据“Sally likes pandas”和“they are lovely”可知，此处表示原因。故选C。
23．A
【详解】句意：人们经常送我扇子作为礼物，因为他们知道我喜欢扇子。
考查从属连词辨析。because因为；while当……时候；so因此；before在……之前。由“People often give me fans as presents…they know I like them”可知，人们送扇子给我是因为我喜欢扇子，应用because引导原因状语从句。故选A。
24．B
【详解】句意：全红禅在比赛中表现得很好，因为她日夜练习。
考查连词。although尽管；because因为；so所以；but但是。前一句表示她在比赛中表现得好，后一句表示她日夜练习，前后表示因果关系，后一句是原因，因此用because引导原因状语从句，故选B。
25．D
【详解】句意：——据说北京烤鸭很有名，很好吃。——好吧，既然我们在这里，为什么不去餐馆点一些呢？
考查连词辨析。unless除非；though尽管；whenever无论何时；since既然。根据“...we’re here, why not go to the restaurant and order some”可知，“我们在这里”是“点餐”的原因，since引导原因状语从句。故选D。
26．D
【详解】句意：大连的许多老建筑看起来很漂亮，因为工人们使它们看起来像新的一样。
考查连词辨析。while当……的时候；if如果；although虽然；because因为。根据“workers make them look as good as new.”可知，这里是由because引导的原因状语从句。故选D。
27．A
【详解】句意：既然您已经了解了它的工作原理，为什么不亲自尝试一下呢？
考查连词。Now that既然，是连词；So that以便于，是连词；In order to为了，是介词短语；No longer不再，是副词短语。此处接从句，用连词，排除CD两项。建议你自己尝试一下，是因为你已经了解了它的工作原理，因此用now that引导原因状语从句，故选A。
28．A
【详解】句意：既然你今天有空，你能帮我做家务吗？
考查从属连词辨析。Since既然；Though尽管；Unless除非；Until直到。根据“you are free today”可知，今天有空，就可以帮忙做家务，此处应用since引导原因状语从句。故选A。
29．B
【详解】句意；——你的英语进步很大！你真努力啊！——我不敢相信。我能成功因为我尽最大努力了。
考查连词辨析。since自从，既然；because因为；if如果；until直到。根据“I could make it … I tried my best”可知，成功是因为尽了最大的努力，空格后表示成功的直接原因，用because引导原因状语从句，故选B。
30．A
【详解】句意：我们家想买电动汽车，因为它们产生的空气污染少。
考查连词辨析。because因为；so所以；but但是；and和。根据“Our family would like to buy electric cars…they produce less air pollution.”可知，后句是前句的原因，因此此处用“because”来连接。故选A。
31．A
【详解】句意：很难和我们的中学说再见，因为我们都有许多记得的快乐日子。
考查连词辨析。because因为；before在……之前；until直到；unless除非。根据“It’s hard to say goodbye to our middle school …we all have many happy days to remember.”可知，因为度过了许多快乐的日子，所以很难和我们的中学说再见，用because引导原因状语从句，故选A。
32．A
【详解】句意：一些学生花更多的时间在学校，因为学校提供课后照顾服务。
考查连词辨析。because因为；and和；so因此；but但是。根据“Some students are spending more time at school”和“schools are doing after-hours caretaking services”可知，一些学生在学校停留的时间更长，是因为学校提供了课后照顾服务；前后句为因果关系，前果后因，应用because连接。故选A。
33．C
【详解】句意：许多人更喜欢读纸质书，因为它们读起来很舒服。
考查连词辨析。and和；but但是；because因为；so因此。“they are comfortable to read”是许多人喜欢读纸质书的原因，前果后因，用because引导原因状语从句。故选C。
34．A
【详解】句意：我们很高兴，因为我们赢得了演讲比赛。
考查连词辨析。because因为；but但是；or或者；so所以。分析“We were very happy...we won the speech competition.”可知，前后两句是因果关系，前果后因，应用because引导原因状语从句。故选A。
35．B
【详解】句意：人生之路从不一帆风顺，因为它充满了起伏。
考查连词。though虽然；since因为；while然而；unless除非。根据“The course of life never runs smoothly...it is full of ups and downs.”可知，此空应是since，引导原因状语从句，表示因为人生充满了起伏，所以人生之路从来都不是一帆风顺的。故选B。
36．C
【详解】句意：因为我尽了最大的努力，我的生活中出现了很多美妙的事情。
考查连词辨析。if如果；though虽然；because因为；until直到。“I tried my best”是“There are so many wonderful things that have come into my life”的原因，用because引导原因状语从句。故选C。
37．A
【详解】句意：——你好，迈克！你愿意和我一起放风筝吗？——我很想去，但是我不能去，因为我必须先完成我的问题调查。
考查连词辨析。because因为；until直到；so因此；while当……时。“I have to finish my question survey first”是“I’d like to go but I can’t”的原因，用because引导原因状语从句。故选A。
38．B
【详解】句意：因为雨下得很大，这家人不得不住在旅馆里。
考查从属连词。although尽管；because因为；until直到；unless除非。根据语境可知，此处存在因果关系，空格后为原因，故应用because引导原因状语从句。故选B。
39．B
【详解】句意：这可能是一个男孩的房间，因为衣服看起来像男孩的衣服。
考查连词辨析。when当……时候；because因为；but但是；so所以。分析题干可知，前后句是因果关系，前果后因，应用because引导原因状语从句，故选B。
40．D
【详解】句意：——汤姆，你今天怎么看起来这么累？——哦，我没睡好，因为我昨天工作了12个小时。
考查连词辨析。although尽管；since自从；until直到；because因为。根据“I didn’t get enough sleep”和“I have worked for 12 hours yesterday.”可知，汤姆睡眠不足，是因为昨天连续工作了12个小时，前后是因果关系，故用because。故选D。
41．B
【详解】句意：——你为什么喜欢听音乐？——因为它让我感到放松。
考查从属连词。Because of因为，后跟短语；Because因为，后跟句子；Since既然；As由于。根据“Why do you like listening to music ”可知，Why提问的特殊疑问句询问原因，需要使用Because回答。故选B。
42．B
【详解】句意：既然我们做了承诺，让我们试着遵守它吧。
考查连词辨析。Whether是否；Since既然；Though虽然；Unless除非。根据“we’ve made the promise, let’s try to keep it.”可知前后是因果关系，用since引导原因状语从句。故选B。
43．B
【详解】句意：由于新型冠状病毒仍在快速传播，接种疫苗是非常必要的。
考查连词辨析。before在……之前；since由于；although尽管；unless除非。根据“ the COVID-19 is still spreading rapidly, getting a vaccine(疫苗) is quite necessary”可知，“新型冠状病毒仍在快速传播”是接种疫苗的原因，用since引导原因状语从句，故选B。
44．B
【详解】句意：既然我们已经许下了诺言，就让我们信守诺言，不要轻易放弃。
考连词。Whether是否；Since既然；Though虽然；Unless除非；根据“we’ve made the promise, let’s keep to it and not give up easily.”可知，此处表达的是因果关系，应用since连接，引导原因状语从句，故选B。
45．C
【详解】句意：安迪，既然你还没有完成作业，我们只好不带你去打篮球了。
考查连词辨析。although虽然，尽管；until直到；since既然；whenever无论何时。“you haven’t finished your homework”是后句“we have to play basketball without you”的原因，所以用since引导原因状语从句，故选C。
46．A
【详解】句意：既然这台电脑不能工作，让我们试另一台吧。
考查从属连词辨析。Since因为，既然；Because因为；After在……之后；While在……期间。根据“this computer doesn’t work”可知，电脑不工作，是很明显的原因，且置于主句之前，因此应用since来引导原因状语从句。故选A。
47．B
【详解】句意：——你认为我今天应该穿一件橙色的衬衫吗？——是的。因为橙色能给你带来好运，它对你的面试很有好处。
考查连词辨析。And和；As由于；But但是；While当……时。根据“orange can bring you good luck, it is good for your interview”可知，前后句是因果关系，用as引导原因状语从句，故选B。
48．A
【详解】句意：我们想买电动汽车，因为它们产生的空气污染更少。
考查连词辨析。because因为；so因此；though尽管；but但是。上文“想买电动汽车”和下文“电动汽车产生较少空气污染”之间是因果关系，前者是结果，后者表原因，故用because连接。故选A。
49．A
【详解】句意：既然你父亲已经康复了，你再也没有什么可担心的了。
考查连词辨析。Since因为，既然；Before在……之前；Although尽管；While当……时。根据“you no longer have anything to worry about”可知，因为父亲已经康复了，所以不需要担心了；故选A。
50．C
【详解】句意：伊莱恩早会迟到了，因为她错过了早班车。
考查从属连词辨析。unless除非；though尽管；because因为；until直到。结合句意可知，前句“Elaine was late for the morning meeting”与后句“she missed the early bus.”表示因果关系，应用because引导原因状语从句。故选C。