Unit 1 Teenagers today 单元Grammar：条件状语从句和原因状语从句精讲精练70题-2026-2027学年九年级英语上册语法词汇综合专练（外研版新教材）

**基本信息** 聚焦条件与原因状语从句，以“知识梳理-典例精析-易错警示-分层精练”构建系统性训练，强化语言运用与逻辑思维。 **专项设计** |模块|题量/典例|方法提炼|知识逻辑| |----|-----------|----------|----------| |条件状语从句|2核心知识+2典例|引导词辨析（if/unless/as long as）、“主将从现”规则|从引导词含义到时态规则，构建“概念-规则-应用”链条| |原因状语从句|3核心知识+3典例|引导词语气差异（because/since/as/for）、because与because of用法|通过语气强弱对比，建立“原因表达-语境匹配”逻辑| |综合运用与易错点|4易错点+1综合典例|unless与if逻辑转换、避免连词连用（because/so）|整合两类从句，通过正误对比突破高频易错点|

学校:姓名:班级:考号: Unit 1 Teenagers today 单元Grammar:条件状语从句和原因状语从句精讲精练70题 语法知识精讲 模块一 条件状语从句 核心知识 一 | 条件状语从句概述 知识梳理 条件状语从句表示主句动作发生的条件,由 if(如果)、unless(除非=ifnot)、as long as(只要)等引导。从句可放在主句前或后,前置时用逗号隔开。 引导词 含义 例句 if 如果 If it rains tomorrow, we will stay at home. unless 除非(=ifnot) You will fail unless you study hard. as long as 只要 You can borrow the book as long as you return it. 【典例精析】 例1 You will miss the early bus you hurry up. A. if B. unless C. when D. because 【答案】B 【解析】unless = ifnot,意为"除非你快点,否则你会错过早班车"。if 填入句意变为"如果你快点,你会错过早班车",逻辑不通;when 表时间,because 表原因,均不合语境。 核心知识 二 | 条件状语从句时态规则 知识梳理 主句(将来时/情态动词/祈使句)+ if + 从句(一般现在时) if 引导的条件状语从句中,若主句表示将来,从句用一般现在时表将来,即"主将从现"。具体分三种情况: 规则 主句 例句 主将从现 一般将来时(will+动原) If he comes, I will tell him. 主情从现 含情态动词(can/may/should) If you finish early, you may leave. 主祈从现 祈使句(动词原形开头) If you see him, please tell me. 拓展 unless, as long as 引导的条件状语从句同样遵循"主将从现"规则。 【典例精析】 例2 If it fine tomorrow, we a picnic in the park. A. is; have B. will be; will have C. is; will have D. will be; have 【答案】C 【解析】if 引导条件状语从句,遵循"主将从现":从句用一般现在时 is,主句用一般将来时 will have。 模块二 原因状语从句 核心知识 三 | 原因状语从句引导词辨析 知识梳理 原因状语从句表示主句动作发生的原因,由 because, since, as, for 等引导。四者语气强弱不同,用法有别: 引导词 语气 用法 例句 because 最强 回答why的提问;表直接原因;可放句首或句中 He was late because he missed the bus. since 较强 表"既然",已知的、显然的原因;多放句首 Since everyone is here, let's begin. as 较弱 表"由于",显而易见的原因;多放句首 As it was late, we went home. for 最弱 表补充说明的原因;不放句首,前加逗号 He went to bed, for he was tired. 【典例精析】 例3 —Why are you late for school? — I missed the early bus. A. Because B. Since C. As D. For 【答案】A 【解析】回答 why 的提问必须用 because。since/as 表已知或显而易见的原因,for 表补充说明且不放句首,均不能回答 why。 核心知识 四 | because 与 so 不连用 / because 与 because of 知识梳理 一、because 与 so 不能连用 because 表原因,so 表结果,二者 不能同时出现在一个句子中,只能择一使用。类似规则:although/though 与 but 不连用。 正确 Because he was ill, he didn't go to school. 错误 Because he was ill, so he didn't go to school. 二、because 与 because of 的区别 词组 用法 例句 because 连词,后接从句(主语+谓语) He was late because it rained. because of 介词短语,后接名词/代词/动名词 He was late because of the rain. 【典例精析】 例4 He didn't go to school his serious illness. A. because B. because of C. so D. as 【答案】B 【解析】his serious illness 是名词短语,不是从句,需用介词短语 because of 后接名词。because/as 后接从句,so 表结果,均不合结构。 核心知识 五 | 综合运用与易错点 知识梳理 条件状语从句与原因状语从句常混合考查,需根据语境逻辑判断连词类型,并注意时态规则和连词不连用原则。 【典例精析】 例5 You will not remember these new words you understand them. A. if B. unless C. because D. so 【答案】B 【解析】unless = ifnot,意为"除非你理解这些单词,否则你不会记住"。if 填入句意相反;because/so 表因果,不合语境逻辑。 核心知识 突破篇 | 重难点 易错点警示 易错点一:if 从句误用将来时 正确 If it rains tomorrow, we will stay home. 错误 If it will rain tomorrow, we will stay home. 解析:if 引导条件状语从句遵循"主将从现",从句用一般现在时表将来,不能用 will。 易错点二:because 与 so 连用 正确 Because he was tired, he went to bed. 错误 Because he was tired, so he went to bed. 解析:because 表原因,so 表结果,二者不能同时出现在一个句子中,择一使用。 易错点三:because 与 because of 混淆 正确 He was late because of the heavy snow. 错误 He was late because the heavy snow. 解析:because 后接从句,because of 后接名词/代词/动名词。the heavy snow 是名词短语,用 because of。 易错点四:unless 与 if 逻辑混淆 正确 You will fail unless you study hard. 错误 You will fail if you study hard. 解析:unless = ifnot,意为"除非努力否则失败";if 填入后逻辑变为"如果努力就会失败",句意相反。 语法知识精练 一、单项选择 1.You won’t pass the PE exam successfully you exercise every day. A.if B.unless C.as long as D.since 2. you read more good books, your writing style will become better. A.Although B.Unless C.If D.Because 3. you don’t get up early, you will miss the first class. A.Unless B.If C.Though D.Before 4.You will be late for school you get up right now. A.if B.unless C.when D.until 5.You will fall behind others you keep working hard. A.if B.unless C.when D.because 6.Keeping a reading diary is useful it helps me understand the ideas better. A.because B.though C.until D.unless 7.My grandpa listens to Beijing Opera every morning it helps him relax. A.although B.because C.unless D.so 8.Daniel feels stressed he has too many after-school courses at weekends. A.though B.until C.because D.if 9.—Why do you prefer this song? — it has a beautiful melody. A.Because B.For C.Since D.As 10.I prefer soft music, it makes me feel peaceful. A.while B.since C.as D.because 11.She practices the piano every day, she wants to be a pianist. A.because B.for C.so D.but 12. you love singing, why not take part in the talent show? A.Because B.Since C.For D.As 13.She didn’t go to the theatre she had already seen the opera. A.because B.since C.for D.as 14. he is interested in electronic music, he joined the music club. A.If B.Since C.For D.Though 15.I want to know if it tomorrow. If it , we will have a picnic. A.rains; will rain B.is rainy; doesn’t rain C.will rain; will be rainy D.will be rainy; doesn’t rain 16.The sentence “You will fail unless you keep trying.” has the same meaning as “”. A.You will fail if you keep trying. B.You won’t fail if you keep trying. C.You won’t fail unless you keep trying. D.You will fail though you keep trying. 17.Which of the following sentences is correct? A.Unless you will practice hard, you won’t make progress. B.Unless you practice hard, you won’t make progress. C.You won’t make progress unless you don’t practice hard. D.Unless you don’t practice hard, you won’t make progress. 18.I won’t be able to go to the cinema with you I finish my volunteer work this weekend. A.as B.unless C.since D.if 19. you see John this morning, please ask him he will have time tomorrow. A.Whether; if B.If; whether C.Whether; whether or not D.If; if or not 20.The art will be popular again young people are interested in it. A.if B.because C.although D.when 21.—Would you like to go hiking with us tomorrow? —Sure, I am busy. A.since B.until C.when D.unless 22.You can hardly imagine how amazing the film Zootopia 2 (《疯狂动物城2》) is you see it for yourself. A.unless B.if C.although D.since 23.I don’t know he will come tomorrow. he comes, I’ll tell you. A.if; Whether B.whether; That C.if; If D.that; If 24. you save some money each month, you will be able to buy that bike soon. A.Unless B.If C.Because D.Though 25.— It’s said that Yangzhou Fried Rice is very famous and delicious. — Well, we’re here, why not go to the restaurant and order some? A.unless B.since C.until D.though 26.The word “as” in the sentence “As he likes the sounds of nature, Tan uses them a lot in his music.” is used to . A.show purpose B.show reason C.show result D.show time 27.She went back to live with her mother she couldn’t afford a flat for herself. A.while B.but C.since D.so 28.—It’s widely known that xiaolongbao is a local delicacy. —Well, we have been in Wuxi, it would be a shame to leave without tasting it. A.though B.unless C.since D.until 29. Hefei’s drone industry develops fast, it has won wide attention across China. A.Although B.Because C.While D.Unless 30.She didn’t attend the music class she was feeling unwell. A.since B.as C.because D.for 31.I bought the ticket online I wanted to save time. A.because B.for C.since D.as 32.He waited patiently the concert was completely over before he left, he didn’t want to miss the very last song. A.since; because B.until; as C.as soon as; because D.so; since 33.—Can you guess if they to play soccer with us? —I think they will come if they free. A.will come, will be B.come, will be C.come, are D.will come, are 34.—Do you know if he the job offer? —Unless he a higher salary, I am sure he won’t. A.will receive; accepts B.will accept; receives C.receives; will accept D.accepts; receives 35.You can soon get out of practice you play it every day. A.since B.though C.if D.unless 36.—I’m not sure if he to the party. —If he, I’ll tell you. A.comes; comes B.will come; will come C.comes; will come D.will come; comes 37.—I don’t know if it tomorrow. —Well, if it , the school sports meeting will be put off. A.will rain; will rain B.rains; will rain C.will rain; rains D.rains; rains 38. you stick to practicing speaking English every day you improve your oral English quickly. A.Only if; will B.If; can C.Unless; will D.As long as; can 39.Chances belong to those keep trying. you keep working hard, you’ll succeed sooner or later. A.who, As soon as B.whom, As well as C.who, As long as D.whom, As far as 40.We will have to cancel the outdoor activity the rain stops before noon. A.until B.though C.unless D.because 41.He seldom smoothly completes all his exercises on time he is allowed to depend on the help of the internet. A.unless B.but C.while D.until 42.You won’t understand the poem you read it again and again. A.if B.unless C.because D.so 43.It was Sunday. Marcus didn't need to go to school, he didn't get up until 9 a.m. A.Unless B.When C.Though D.As 44.I didn’t accept his help I wanted to try it myself. A.though B.until C.because D.as soon as 45.—She may need some help she’s new here. —Let’s help her as much as possible. A.though B.unless C.while D.as 46. you know it is harmful, you should stop reading in such a dark place. A.Until B.Unless C.Although D.Since 47.—The light in his room is still on. Do you know why he stays up so late? — prepare for the coming exam. A.In order that B.So that C.In order to D.Because 48.— heavy the snow that is falling in Changzhou is! How can we go to work today? — it is snowing heavily, let’s walk instead of driving. A.What; Because B.What a; Since C.How; Since D.How; Though 49. nicknames are seen as a form of showing no respect for others, next time you want to call someone by his nickname at school, weigh it before you do. A.Unless B.Since C.Until D.Although 50.—Why do you always download music from that particular website? — it offers a wide range of free songs in high quality. A.As B.For C.Because D.Since 二、完成句子 51.既然你已经长大了,就应该学会独立。 you have grown up, you should learn to be independent. 52.I like managing money. It helps me develop a sense of responsibility.(用because合并句子) I like managing money me develop a sense of responsibility. 53.如果你想要成为一名好的倾听者,就要保持专注。(每空一词) If you to be a good listener, focused. 54.如果你记住了他的名字,下次见面时就能让他感到自在。 If you his name, you can make him feel when you meet next time. 55.由于天黑了,我们不得不停止工作。 it was dark, we had to stop working. 56.既然大家都准备好了,我们出发吧。 everyone is ready, let’s set off. 57.He didn’t join the inspiring people club because he was busy with exams. (对划线部分提问) he join the inspiring people club? 58.我并不是因为生气才离开的。 I left, not I was angry. 59.既然你对这首流行歌曲很熟悉,那你能跟着音乐一起唱吗? , can you sing along ? 60.由于桌子被搬走了,我的房间似乎变得更大了。 the table was moved away, my room seemed to get bigger. 61.I don’t use disposable chopsticks. I want to protect the environment.(用because合并句子) I don’t use disposable chopsticks protect the environment. 62.如果这种意外发生,需要道歉。 If such an accident , apologies are needed. 63.You learn the pioneers’ spirits. You will become more brave.(用if合并句子) You will become more brave you learn the pioneers’ spirits. 64.You review your lessons every day. You won’t feel anxious in exams.(合并为一句) You won’t feel anxious in exams you review your lessons every day. 65.You take advantage of learning resources. You will make fast progress. (用if合并句子) You will make fast progress you take advantage of learning resources. 66.如果你必须改变计划,提前让你的朋友知道。 If you have to your plan, let your friends know . 67.He was ill. He didn’t go to school. (合并为含 because 的复合句) He didn’t go to school ill. 68.If you don’t work hard, you will fall behind. (改为同义句,用unless) you work hard, you will fall behind. 69.Unless you keep trying, you won’t achieve your dream. (改为同义句,用ifnot) you trying, you won’t achieve your dream. 70.他认为如果尽最大努力,就可以做好任何事情。 He thinks that he can if he . 试卷第1页,共3页 试卷第1页,共3页 学科网(北京)股份有限公司 $ 学校:___________姓名：___________班级：___________考号：___________ Unit 1 Teenagers today 单元Grammar：条件状语从句和原因状语从句精讲精练70题 语法知识精讲 模块一 · 条件状语从句 核心知识 一 | 条件状语从句概述 ▎ 知识梳理 条件状语从句表示主句动作发生的条件，由 if（如果）、unless（除非=if...not）、as long as（只要）等引导。从句可放在主句前或后，前置时用逗号隔开。 引导词 含义 例句 if 如果 If it rains tomorrow, we will stay at home. unless 除非（=if...not） You will fail unless you study hard. as long as 只要 You can borrow the book as long as you return it. 【典例精析】 例1 You will miss the early bus ______ you hurry up. A. if B. unless C. when D. because 【答案】B 【解析】unless = if...not，意为"除非你快点，否则你会错过早班车"。if 填入句意变为"如果你快点，你会错过早班车"，逻辑不通；when 表时间，because 表原因，均不合语境。 核心知识 二 | 条件状语从句时态规则 ▎ 知识梳理 主句（将来时/情态动词/祈使句）+ if + 从句（一般现在时） if 引导的条件状语从句中，若主句表示将来，从句用一般现在时表将来，即"主将从现"。具体分三种情况： 规则 主句 例句 主将从现 一般将来时（will+动原） If he comes, I will tell him. 主情从现 含情态动词（can/may/should） If you finish early, you may leave. 主祈从现 祈使句（动词原形开头） If you see him, please tell me. 💡 拓展 unless, as long as 引导的条件状语从句同样遵循"主将从现"规则。 【典例精析】 例2 If it ______ fine tomorrow, we ______ a picnic in the park. A. is; have B. will be; will have C. is; will have D. will be; have 【答案】C 【解析】if 引导条件状语从句，遵循"主将从现"：从句用一般现在时 is，主句用一般将来时 will have。 模块二 · 原因状语从句 核心知识 三 | 原因状语从句引导词辨析 ▎ 知识梳理 原因状语从句表示主句动作发生的原因，由 because, since, as, for 等引导。四者语气强弱不同，用法有别： 引导词 语气 用法 例句 because 最强 回答why的提问；表直接原因；可放句首或句中 He was late because he missed the bus. since 较强 表"既然"，已知的、显然的原因；多放句首 Since everyone is here, let's begin. as 较弱 表"由于"，显而易见的原因；多放句首 As it was late, we went home. for 最弱 表补充说明的原因；不放句首，前加逗号 He went to bed, for he was tired. 【典例精析】 例3 —Why are you late for school? —______ I missed the early bus. A. Because B. Since C. As D. For 【答案】A 【解析】回答 why 的提问必须用 because。since/as 表已知或显而易见的原因，for 表补充说明且不放句首，均不能回答 why。 核心知识 四 | because 与 so 不连用 / because 与 because of ▎ 知识梳理 ◆ 一、because 与 so 不能连用 because 表原因，so 表结果，二者 不能同时出现在一个句子中，只能择一使用。类似规则：although/though 与 but 不连用。 ✅ 正确 Because he was ill, he didn't go to school. ❌ 错误 Because he was ill, so he didn't go to school. ◆ 二、because 与 because of 的区别 词组 用法 例句 because 连词，后接从句（主语+谓语） He was late because it rained. because of 介词短语，后接名词/代词/动名词 He was late because of the rain. 【典例精析】 例4 He didn't go to school ______ his serious illness. A. because B. because of C. so D. as 【答案】B 【解析】his serious illness 是名词短语，不是从句，需用介词短语 because of 后接名词。because/as 后接从句，so 表结果，均不合结构。 核心知识 五 | 综合运用与易错点 ▎ 知识梳理 条件状语从句与原因状语从句常混合考查，需根据语境逻辑判断连词类型，并注意时态规则和连词不连用原则。 【典例精析】 例5 You will not remember these new words ______ you understand them. A. if B. unless C. because D. so 【答案】B 【解析】unless = if...not，意为"除非你理解这些单词，否则你不会记住"。if 填入句意相反；because/so 表因果，不合语境逻辑。 核心知识 突破篇 | 重难点 · 易错点警示 ▎ 易错点一：if 从句误用将来时 ✅ 正确 If it rains tomorrow, we will stay home. ❌ 错误 If it will rain tomorrow, we will stay home. 解析：if 引导条件状语从句遵循"主将从现"，从句用一般现在时表将来，不能用 will。 ▎ 易错点二：because 与 so 连用 ✅ 正确 Because he was tired, he went to bed. ❌ 错误 Because he was tired, so he went to bed. 解析：because 表原因，so 表结果，二者不能同时出现在一个句子中，择一使用。 ▎ 易错点三：because 与 because of 混淆 ✅ 正确 He was late because of the heavy snow. ❌ 错误 He was late because the heavy snow. 解析：because 后接从句，because of 后接名词/代词/动名词。the heavy snow 是名词短语，用 because of。 ▎ 易错点四：unless 与 if 逻辑混淆 ✅ 正确 You will fail unless you study hard. ❌ 错误 You will fail if you study hard. 解析：unless = if...not，意为"除非努力否则失败"；if 填入后逻辑变为"如果努力就会失败"，句意相反。 语法知识精练 一、单项选择 1．You won’t pass the PE exam successfully ________ you exercise every day. A．if B．unless C．as long as D．since 【答案】B 【详解】句意：除非你每天锻炼，否则你不会成功通过体育考试。 if如果；unless除非；as long as只要；since自从/既然。根据“You won’t pass the PE exam successfully... you exercise every day.”可知，主句为否定句，此处表示否定条件，意为“除非……否则不……”，unless相当于if not，符合语境。 2．________ you read more good books, your writing style will become better. A．Although B．Unless C．If D．Because 【答案】C 【详解】句意：如果你阅读更多的好书，你的写作风格将会变得更好。 Although虽然；Unless除非；If如果；Because因为。根据句意可知，前句是后句的条件，表示“如果”多读书，写作会变好，if引导条件状语从句符合语境。 3．________ you don’t get up early, you will miss the first class. A．Unless B．If C．Though D．Before 【答案】B 【详解】句意：如果你不早起，你就会错过第一节课。 Unless除非；If如果；Though尽管；Before在……之前。根据后句“you will miss the first class”的结果逻辑可知，此处表示“如果不早起就会迟到”的假设条件关系，应填If。 4．You will be late for school ________ you get up right now. A．if B．unless C．when D．until 【答案】B 【详解】句意：你上学就要迟到了，除非你现在立刻起床。 if如果；unless除非；when当……时候；until直到。根据前句“You will be late for school”的负面结果逻辑可知，此处表示“只有立刻起床才能避免迟到”的反向条件关系，应填unless。 5．You will fall behind others ________ you keep working hard. A．if B．unless C．when D．because 【答案】B 【详解】句意：你将会落后于别人，除非你继续努力学习。 if如果；unless除非；when当……时候；because因为。根据“You will fall behind others...you keep working hard.”可知，不持续努力就会落后，unless相当于if … not “如果不”，符合句子逻辑。 6．Keeping a reading diary is useful ________ it helps me understand the ideas better. A．because B．though C．until D．unless 【答案】A 【详解】句意：写阅读日记是有用的，因为它帮助我更好地理解观点。 because因为；though虽然；until直到；unless除非。根据“it helps me understand the ideas better”可知，后半句解释了写阅读日记有用的原因，用because引导原因状语从句。 7．My grandpa listens to Beijing Opera every morning ________ it helps him relax. A．although B．because C．unless D．so 【答案】B 【详解】句意：我爷爷每天早上听京剧，因为它帮助他放松。 although虽然；because因为；unless除非；so所以。根据“it helps him relax”可知，后半句解释了爷爷听京剧的原因，前后句是因果关系，空处表示“因为”，应用because。 8．Daniel feels stressed ________ he has too many after-school courses at weekends. A．though B．until C．because D．if 【答案】C 【详解】句意：丹尼尔感到压力很大，因为他周末有太多课外辅导班。 though虽然（引导让步状语从句）；until直到（引导时间状语从句）；because因为（引导原因状语从句）；if如果（引导条件状语从句）。根据“Daniel feels stressed”与“he has too many after-school courses”可知，后一分句是前一分句的原因，故用because。 9．—Why do you prefer this song? —________ it has a beautiful melody. A．Because B．For C．Since D．As 【答案】A 【详解】句意：——你为什么更喜欢这首歌？——因为它有优美的旋律。 Because因为；For因为；Since既然；As由于。根据问句“Why do you prefer this song?”可知，询问原因，回答Why引导的疑问句通常用Because开头，故选Because。 10．I prefer soft music, ________ it makes me feel peaceful. A．while B．since C．as D．because 【答案】D 【详解】句意：我更喜欢轻音乐，因为它让我感到平静。 while然而；since既然，由于；as由于；because因为。“it makes me feel peaceful”是“prefer soft music”的直接原因，语气较强，应用because引导原因状语从句。 11．She practices the piano every day, ________ she wants to be a pianist. A．because B．for C．so D．but 【答案】A 【详解】句意：她每天练习钢琴，因为她想成为一名钢琴家。 because因为；for因为（不表示直接原因，只是说话人根据前面事实推测、补充说明理由）；so所以；but但是。根据“She practices the piano every day”可知这是行为结果，而“she wants to be a pianist”是原因，前后句为因果关系，且后句解释原因，应用because引导。 12．________ you love singing, why not take part in the talent show? A．Because B．Since C．For D．As 【答案】B 【详解】句意：既然你喜欢唱歌，为什么不参加才艺表演呢？ Because（因为），侧重直接回答why提出的问题；Since（既然），引导已知、显而易见的原因，常置于句首；For（因为），并列连词，不能放在句首；As（由于），语气较弱。本句是基于已知事实给出建议，since表示“既然”，符合语境，因此应选Since。 13．She didn’t go to the theatre ________ she had already seen the opera. A．because B．since C．for D．as 【答案】A 【详解】句意：她没有去剧院，因为她已经看过这部歌剧了。 because因为；since因为，既然；for因为（表示补充说明）；as因为，当……时。since、as表示已知原因，语气较弱；for不能放在句首，通常用于主句后补充说明原因。because表示直接、明确的原因，符合“没去剧院是因为已经看过歌剧”的语境。应填because。 14．________ he is interested in electronic music, he joined the music club. A．If B．Since C．For D．Though 【答案】B 【详解】句意：因为他对电子音乐感兴趣，所以他加入了音乐俱乐部。 If如果；Since因为/由于；For因为；Though虽然。根据前后句逻辑可知，“对电子音乐感兴趣”是“加入音乐俱乐部”的原因/背景依据。For作连词表原因时，通常不放在句首，而是放在主句之后作为补充说明。Since侧重基于已知事实/背景的顺理成章推导（语气贴合“因兴趣而加入俱乐部”的逻辑），因此选Since。 15．I want to know if it ________ tomorrow. If it ________, we will have a picnic. A．rains; will rain B．is rainy; doesn’t rain C．will rain; will be rainy D．will be rainy; doesn’t rain 【答案】D 【详解】句意：我想知道明天是否会是雨天。如果明天不下雨，我们将去野餐。 第一空if引导宾语从句，意为“是否”，根据时间状语tomorrow可知应用一般将来时will be rainy；第二空if引导条件状语从句，意为“如果”，遵循“主将从现”原则，主句是一般将来时，从句应用一般现在时，且根据语境“去野餐”可知需表示否定“不下雨”，主语it是第三人称单数，否定形式用doesn’t rain。 16．The sentence “You will fail unless you keep trying.” has the same meaning as “________”. A．You will fail if you keep trying. B．You won’t fail if you keep trying. C．You won’t fail unless you keep trying. D．You will fail though you keep trying. 【答案】B 【详解】句意：句子“You will fail unless you keep trying.”与“You won’t fail if you keep trying.”意思相同。 You will fail if you keep trying.如果你继续尝试，你会失败；You won’t fail if you keep trying.如果你继续尝试，你不会失败；You won’t fail unless you keep trying.除非你继续尝试，否则你不会失败；You will fail though you keep trying.尽管你继续尝试，你会失败。unless意为“除非=如果不”，原句意为“如果你不继续尝试，你会失败”，即“如果你继续尝试，你不会失败”。 17．Which of the following sentences is correct? A．Unless you will practice hard, you won’t make progress. B．Unless you practice hard, you won’t make progress. C．You won’t make progress unless you don’t practice hard. D．Unless you don’t practice hard, you won’t make progress. 【答案】B 【详解】句意：以下句子正确的是哪一项？ 在unless（除非，如果不）引导的条件状语从句中，通常需要遵循“主将从现”原则，即主句用一般将来时，从句用一般现在时来表示将来的动作。选项A错误在其引导的从句中使用了将来时“will practice”；选项C和D的错误在于unless本身已含有否定含义（相当于if...not），在它引导的从句中不应再使用否定词，否则会造成语义重复和逻辑混乱。因此，只有选项B语法正确，句意通顺，意为“除非你努力练习，否则你不会进步”。 18．I won’t be able to go to the cinema with you ________ I finish my volunteer work this weekend. A．as B．unless C．since D．if 【答案】B 【详解】句意：这个周末除非我完成志愿工作，否则我没法和你一起去看电影。 as当……时；unless除非，如果不；since自从，既然；if如果。主句为否定形式“won’t”，句子逻辑是：只有做完志愿工作才能去看电影。unless等同于if...not，意为“除非”，贴合本句“不完成工作就不能去”的否定条件逻辑。故选unless。 19．________ you see John this morning, please ask him ________  he will have time tomorrow. A．Whether; if B．If; whether C．Whether; whether or not D．If; if or not 【答案】B 【详解】句意：如果你今早见到约翰，请问问他明天是否有空。 if如果、是否；whether是否。第一空引导条件状语从句，表示“如果”，使用If；第二空引导宾语从句，表示“是否”，可用whether，所以用If; whether。 20．The art will be popular again ________ young people are interested in it. A．if B．because C．although D．when 【答案】A 【详解】句意：如果年轻人对它感兴趣，这门艺术将会再次流行起来。 if如果；because因为；although虽然；when当……时候。“The art will be popular again”是将来的结果，“young people are interested in it”是达成该结果的条件，因此空处填写if引导条件状语从句。 21．—Would you like to go hiking with us tomorrow? —Sure, ________ I am busy. A．since B．until C．when D．unless 【答案】D 【详解】句意：——你明天想和我们一起去远足吗？——当然，除非我很忙。 since自从，既然；until直到；when当……的时候；unless除非。根据答语“Sure”可知说话人愿意去，后半句“I am busy”是不能去的例外条件，用unless引导条件状语从句。 22．You can hardly imagine how amazing the film Zootopia 2 (《疯狂动物城2》) is ________ you see it for yourself. A．unless   B．if   C．although   D．since 【答案】A 【详解】句意：你几乎想象不出《疯狂动物城2》这部电影有多精彩，除非你亲自观看。 unless除非；if如果；although虽然；since自从/既然。根据句子逻辑，除非亲自观影，否则无法想象影片有多精彩，应填unless。 23．I don’t know ________ he will come tomorrow. ________ he comes, I’ll tell you. A．if; Whether B．whether; That C．if; If D．that; If 【答案】C 【详解】句意：我不知道他明天是否会来。如果他来，我就告诉你。 if是否（引导宾语从句，表示“是否”；引导条件状语从句，表示“如果”）；Whether是否（也可引导宾语从句，但常与or not连用或放句首）；That无实义（引导陈述句，不表疑问）。第一空：if引导宾语从句，意为“是否”，用于表达不确定的疑问，符合“I don’t know”的语境；第二空：if引导条件状语从句，意为“如果”，遵循“主将从现”原则，从句用一般现在时表将来，位于句首首字母需大写为If。 24．________ you save some money each month, you will be able to buy that bike soon. A．Unless B．If C．Because D．Though 【答案】B 【详解】句意：如果你每个月存一些钱，你很快就能买那辆自行车了。 Unless除非（引导条件状语从句）；If如果（引导条件状语从句）；Because因为（引导原因状语从句）；Though虽然（引导让步状语从句）。根据前后句逻辑关系可知，前半句是后半句的条件，表示“如果”每月存钱就能买自行车，故选用If。 25．— It’s said that Yangzhou Fried Rice is very famous and delicious. — Well, ________ we’re here, why not go to the restaurant and order some? A．unless B．since C．until D．though 【答案】B 【详解】句意：——据说扬州炒饭非常有名且美味。——嗯，既然我们在这儿，为什么不去餐厅点一些呢？ unless除非；since既然；until直到；though尽管。根据“we’re here, why not go to the restaurant and order some?”可知，后半句是基于前半句“我们在这儿”这一事实提出的建议，前后构成因果关系，应用since引导原因状语从句。 26．The word “as” in the sentence “As he likes the sounds of nature, Tan uses them a lot in his music.” is used to ________. A．show purpose B．show reason C．show result D．show time 【答案】B 【详解】句意：“As”在句子“因为他喜欢大自然的声音，所以谭先生经常在他的音乐中使用它们。”中用于表示原因。 show purpose表示目的；show reason表示原因；show result表示结果；show time表示时间。根据句意可知，前半句“他喜欢大自然的声音”是后半句“谭先生经常在他的音乐中使用它们”的原因，as在此处引导原因状语从句，表示原因，符合show reason的描述。 27．She went back to live with her mother ________ she couldn’t afford a flat for herself. A．while B．but C．since D．so 【答案】C 【详解】句意：她回去和母亲一起住，因为她自己负担不起一套公寓。 while当……时/然而；but但是；since因为；so所以。根据“She went back to live with her mother ... she couldn’t afford a flat for herself”可知，空后内容是前文“回去和母亲住”的原因，需要表示“因为”的连词，应填since。 28．—It’s widely known that xiaolongbao is a local delicacy. —Well, ________ we have been in Wuxi, it would be a shame to leave without tasting it. A．though B．unless C．since D．until 【答案】C 【详解】句意：——众所周知，小笼包是当地美食。——嗯，既然我们已经在无锡了，如果不尝尝就离开会很遗憾。 though虽然；unless除非；since既然；until直到。根据“it would be a shame to leave without tasting it”可知，说话人认为应该尝尝小笼包，原因是“we have been in Wuxi”，前后是因果关系，用since表原因。 29．________ Hefei’s drone industry develops fast, it has won wide attention across China. A．Although B．Because C．While D．Unless 【答案】B 【详解】句意：因为合肥的无人机产业发展迅速，它在全国范围内赢得了广泛关注。 Although虽然；Because因为；While然而/当……时；Unless除非。根据题干“develops fast”与“has won wide attention”可知，发展快是赢得关注的原因，应用Because引导原因状语从句，应填Because。 30．She didn’t attend the music class ________ she was feeling unwell. A．since B．as C．because D．for 【答案】C 【详解】句意：她没有上音乐课，因为她身体不舒服。 since用于解释清楚的，双方都明白的原因；as用于解释做某事的原因，语气较弱；because表示直接原因，语气最强；for连接并列句，表示一种补充说明。根据“She didn’t attend the music class...she was feeling unwell.”可知，“她身体不舒服”是“她没上音乐课”的直接核心原因，用because引导原因状语从句。 31．I bought the ticket online ________ I wanted to save time. A．because B．for C．since D．as 【答案】A 【详解】句意：我在网上购票，因为我想节省时间。 because因为，表示直接原因；for因为，表示补充理由；since既然，表示显而易见的理由；as因为，语气较弱。根据“I wanted to save time.”可知，想要节省时间是网上购票的直接理由。应填because。 32．He waited patiently ________ the concert was completely over before he left, ________ he didn’t want to miss the very last song. A．since; because B．until; as C．as soon as; because D．so; since 【答案】B 【详解】句意：他耐心等待直到音乐会完全结束才离开，因为他不想错过最后一首歌。 since自从；because因为；until直到；as因为；as soon as一……就；so所以。until表示“直到”，符合第一空“一直等到音乐会结束”；as引导原因状语从句，解释等待的原因。 33．—Can you guess if they ________ to play soccer with us? —I think they will come if they ________ free. A．will come, will be B．come, will be C．come, are D．will come, are 【答案】D 【详解】句意：——你能猜出他们是否会来和我们一起踢足球吗？ ——如果他们有空，我想他们会来的。 考查动词时态。第一空，根据“Can you guess if they …”可知，此处为if引导的宾语从句，主句时态为一般现在时；从句表示他们将和我们一起踢足球，时态应用一般将来时，其结构为will do，即will come，排除B和C；第二空，根据“they will come if they … free”可知，此处为if引导的条件状语从句，遵循“主将从现”原则；主句为一般将来时，从句则用一般现在时，主语“they”为第三人称复数，be动词应用are，排除A。故选D。 34．—Do you know if he ________ the job offer? —Unless he ________ a higher salary, I am sure he won’t. A．will receive; accepts B．will accept; receives C．receives; will accept D．accepts; receives 【答案】B 【详解】句意：——你知道他是否会接受这个工作吗？——除非他得到更高的薪水，我确定他不会。 考查时态和动词辨析。receive收到；accept接受。根据“Do you know if he … the job offer?”可知，此句是if引导的宾语从句，此处说的是不知道是否会接受，用一般将来时，因此第一个空填will accept；再由“Unless he…a higher salary,”可知，此句是Unless条件状语从句，该从句描述的是除非他得到更高的薪水，这是一个条件，通常使用一般现在时来表示将来。所以，这里应该使用一般现在时“receives”。故选B。 35．You can soon get out of practice ________ you play it every day. A．since B．though C．if D．unless 【答案】D 【详解】句意：除非你每天都练习，否则你很快就会退步。 考查连词辨析。since自从；though尽管；if如果；unless除非。根据“You can soon get out of practice...you play it every day.”可知，此处表示除非你每天都练习，否则很快就会退步，unless引导条件状语从句。故选D。 36．—I’m not sure if he________ to the party. —If he________, I’ll tell you. A．comes; comes B．will come; will come C．comes; will come D．will come; comes 【答案】D 【详解】句意：——我不确定他是否会来参加派对。——如果他来，我会告诉你。 考查宾语从句及条件状语从句的时态。comes为动词第三人称单数形式；will come为动词一般将来时。if引导宾语从句时，意思是 “是否”。这里表达对他将来是否来派对不确定，所以从句要用一般将来时；if引导条件状语从句时，遵循“主将从现”原则，即主句用一般将来时，从句要用一般现在时。故选D。 37．—I don’t know if it _________ tomorrow.         —Well, if it _________, the school sports meeting will be put off. A．will rain; will rain B．rains; will rain C．will rain; rains D．rains; rains 【答案】C 【详解】句意：——我不知道明天是否会下雨。——嗯，如果下雨，校运动会会被推迟。 考查宾语从句和条件状语从句。will rain将会下雨，一般将来时态；rains下雨，一般现在时态。根据“I don’t know if it...tomorrow.”可知，本句为宾语从句，根据时间状语“tomorrow”可知，此处应用一般将来时态；根据“if it...the school sports meeting will be put off.”可知本句为if引导的条件状语从句，遵循主将从现原则，主句用一般将来时态，从句用一般现在时态。故选C。 38．________ you stick to practicing speaking English every day ________ you improve your oral English quickly. A．Only if; will B．If; can C．Unless; will D．As long as; can 【答案】A 【详解】句意：只有你坚持每天练习说英语，你才会快速提高你的英语口语。 考查倒装句和连词辨析。Only if只有……才，引导条件状语从句，且置于句首时，主句用部分倒装结构；If如果，引导条件状语从句，遵循主将从现原则，即主句用一般将来时，从句用一般现在时；Unless除非，引导条件状语从句，遵循主将从现原则；As long as只要，引导条件状语从句，遵循主将从现原则。根据语境及“you improve your oral English quickly”可知，此处是表示“只有……才”的逻辑关系，且主句用了一般将来时，从句用了一般现在时，所以第一空用Only if，第二空用will构成部分倒装结构。故选A。 39．Chances belong to those ________ keep trying. ________ you keep working hard, you’ll succeed sooner or later. A．who, As soon as B．whom, As well as C．who, As long as D．whom, As far as 【答案】C 【详解】句意：机会属于那些不断尝试的人。只要你不断努力，你迟早会成功。 考查定语从句和连词。who谁，在定语从句中作主语；whom谁，在定语从句中作宾语；As soon as一……就；As well as和，也；As long as只要；As far as就……而言。第一空是定语从句，先行词those指人，从句keep trying缺主语，应使用关系代词who；根据“you’ll succeed sooner or later. (你迟早会成功)”可知，此处应表示只要不断努力，用as long as。故选C。 40．We will have to cancel the outdoor activity ________ the rain stops before noon. A．until B．though C．unless D．because 【答案】C 【详解】句意：除非中午前雨停，否则我们将不得不取消户外活动。 until直到 (引导时间状语从句)；though虽然 (引导让步状语从句)；unless除非 (引导条件状语从句，相当于if not)；because因为 (引导原因状语从句)。根据句意，除非中午前雨停，否则我们将不得不取消户外活动，因此应选unless。 41．He seldom smoothly completes all his exercises on time ________ he is allowed to depend on the help of the internet. A．unless B．but C．while D．until 【答案】A 【详解】句意：除非被允许依赖互联网的帮助，否则他很少能顺利按时完成所有练习。   unless除非，如果不；but但是；while而，当……时；until直到。根据句意，“依赖互联网帮助”是“顺利按时完成练习”的条件，且“seldom（很少）”表示否定意义，构成“除非……否则不能完成”的逻辑，应用unless引导条件状语从句。 42．You won’t understand the poem __________ you read it again and again. A．if B．unless C．because D．so 【答案】B 【详解】句意：你不会理解这首诗，除非你一遍又一遍地读它。 if如果；unless除非；because因为；so所以。根据“You won’t understand the poem…you read it again and again.”可知，主句是否定句，从句表示条件，此处意为“除非……否则不……”，unless符合语境。故选B。 43．It was Sunday. _____ Marcus didn't need to go to school, he didn't get up until 9 a.m. A．Unless B．When C．Though D．As 【答案】D 【详解】句意：那是星期天，因为马库斯不需要上学，所以他直到早上9点才起床。A. Unless除非；B. When当…时；C. Though虽然；D. As因为。根据语境：星期天了。因为马库斯不需要上学，所以直到9点才起床。结合选项，显然选项D符合题意，故选D。 44．I didn’t accept his help ________ I wanted to try it myself. A．though B．until C．because D．as soon as 【答案】C 【详解】句意：我没有接受他的帮助因为我想自己尝试一下。though尽管，虽然；until直到…时候；because因为；as soon as一…就…。根据句意可知，空后这句话解释前面这件事的原因，故用because引导原因状语从句，选C。 45．—She may need some help ________ she’s new here. —Let’s help her as much as possible. A．though B．unless C．while D．as 【答案】D 【详解】句意：——她是新来的，可能需要一些帮助。   ——让我们尽可能多地帮助她。 考查连词辨析。though虽然，尽管，引导让步状语从句；unless除非，引导条件状语从句；while当……的时候，引导时间状语从句；as因为，引导原因状语从句。分析句子结构可知，句子“she’s new here.”是前句“She may need some help ”的原因，因此用as引导。故选D。 46． ________ you know it is harmful, you should stop reading in such a dark place. A．Until B．Unless C．Although D．Since 【答案】D 【详解】句意：既然你知道这是有害的，你应该停止在这样一个黑暗的地方阅读。 考查从属连词辨析。Until直到；Unless除非；Although尽管；Since自从；既然。此处前后为因果关系，选since引导的原因状语从句，意为“既然”。故选D。 47．—The light in his room is still on. Do you know why he stays up so late? — _______  prepare for the coming exam. A．In order that B．So that C．In order to D．Because 【答案】C 【详解】句意：—— 他房间的灯还亮着。你知道他为什么这么晚才睡吗？—— 为即将到来的考试做准备。 考查短语辨析。in order that为了，后接句子； so that为了，后接句子； in order to为了，后接短语或单词； because因为，后接句子。根据“prepare for the coming exam”可知，不是完整的句子，结合选项，A、B、D选项均是接完整的句子，因此C符合句意。故选C。 48．—_______ heavy the snow that is falling in Changzhou is! How can we go to work today? —_______ it is snowing heavily, let’s walk instead of driving. A．What; Because B．What a; Since C．How; Since D．How; Though 【答案】C 【详解】句意：——常州下的雪可真大啊！今天我们怎么去上班？——既然雪下得很大，我们走路就不开车了。 考查感叹句和连词。What引导感叹句，后加名词短语；How引导感叹句，后加形容词或副词；because因为；since既然；though尽管。heavy是形容词，故用how引导感叹句；根据“it is snowing heavily, let’s walk instead of driving.”可知，既然下大雪，那就不开车了，用since表示显而易见的原因。故选C。 49．________ nicknames are seen as a form of showing no respect for others, next time you want to call someone by his nickname at school, weigh it before you do. A．Unless B．Since C．Until D．Although 【答案】B 【详解】句意：既然绰号被视为对他人不尊重的一种形式，下次你在学校想称呼别人绰号时，先权衡一下再做。 Unless除非，引导条件状语从句；Since既然、因为，引导原因状语从句；Until直到，引导时间状语从句；Although虽然，引导让步状语从句。根据句意，前后是因果关系，“既然”绰号被视为不尊重，所以要谨慎，因此应选Since。 50．—Why do you always download music from that particular website? —________ it offers a wide range of free songs in high quality. A．As B．For C．Because D．Since 【答案】C 【详解】句意：——你为什么总是从那个特定的网站下载音乐？——因为它提供了各种各样高质量的免费歌曲。 As引导原因状语从句时，所表示的原因是显而易见的已知事实，语气较弱，通常不用于直接回答why引导的特殊疑问句；For是并列连词，不能置于句首直接回答问题，仅用于补充说明理由；Because引导原因状语从句时，用于表示直接的、对方不知道的原因，可以用来回答why引导的特殊疑问句；Since引导原因状语从句时，多表示对方已经知晓的明显理由，语气较弱，不用于直接回应why的提问。本题问句由why引导，需要用because引出直接原因作答。 二、完成句子 51．既然你已经长大了，就应该学会独立。 ________ you have grown up, you should learn to be independent. 【答案】Since 【详解】原句中“既然”是关键词，对应since，表已知事实，句首首字母大写，故填Since。 52．I like managing money. It helps me develop a sense of responsibility.（用because合并句子） I like managing money ________ ________ ________ me develop a sense of responsibility. 【答案】 because it helps 【详解】句意：我喜欢理财，因为它帮助我培养责任感。because引导原因状语从句，承接后面完整分句，主语it指代managing money，谓语动词用helps保持原句时态不变。 53．如果你想要成为一名好的倾听者，就要保持专注。（每空一词） If you ________ to be a good listener, ________ focused. 【答案】 want keep 【详解】句中“想要”和“保持”为关键词，表示“想要”的英文为“want”。在if引导的条件状语从句中，遵循“主祈从现”原则（主句为祈使句，从句用一般现在时），主语是you，第一空故填want。中文“就要保持”表示建议，英文主句中没有主语，说明是祈使句，动词需用原形。“保持专注”常用的英文为“keep focused”，故填keep。 54．如果你记住了他的名字，下次见面时就能让他感到自在。 If you ________ his name, you can make him feel ________ when you meet next time. 【答案】 remember comfortable 【详解】句意：如果你记住了他的名字，下次见面时就能让他感到自在。原句中“记住”和“自在”是关键词，remember意为“记住”，if引导条件状语从句，遵循主将从现，主语you后用动词原形；feel为系动词，后接形容词，comfortable意为“舒适的、自在的”。故填remember；comfortable。 55．由于天黑了，我们不得不停止工作。 ________ it was dark, we had to stop working. 【答案】As 【详解】原句中关键词“由于” 对应as，表附带原因，句首首字母大写。 56．既然大家都准备好了，我们出发吧。 ________ everyone is ready, let’s set off. 【答案】Since 【详解】原句中“既然”是关键词，表示“既然”的连词是since，表已知前提。 57．He didn’t join the inspiring people club because he was busy with exams. (对划线部分提问) ________ __________ he join the inspiring people club? 【答案】 Why didn’t 【详解】句意：他没有加入励志人物社团，因为他忙于备考。划线部分是because引导的原因状语从句，对原因提问要用疑问词Why；原句含有助动词didn’t，变为疑问句时要保留助动词didn’t。 58．我并不是因为生气才离开的。 I left, not ________ I was angry. 【答案】because 【详解】原句中“因为”是关键词，表示“因为”的英文是because，是连词，引导原因状语从句。 59．既然你对这首流行歌曲很熟悉，那你能跟着音乐一起唱吗? _______________________________, can you sing along ______________________________? 【答案】 Since you are very familiar with this pop song to the music 【详解】原句中“既然你对这首流行歌曲很熟悉”以及“跟着音乐”是关键词，“既然”使用连词since引导原因状语从句，位于句子开头，首字母需大写；“对……熟悉”对应短语be familiar with，从句主语为你（you），be动词选用are，“这首流行歌曲”对应this pop song；“跟着……哼唱”为sing along to，“音乐”是the music，故填Since you are very familiar with this pop song；to the music。 60．由于桌子被搬走了，我的房间似乎变得更大了。 ________ ________ the table was moved away, my room seemed to get bigger. 【答案】 Now that 【详解】句中缺少关键词“由于”，可用now that表示。now that“既然，由于”，后接从句，句首首字母大写。 61．I don’t use disposable chopsticks. I want to protect the environment.（用because合并句子） I don’t use disposable chopsticks ________ ________ ________ ________ protect the environment. 【答案】 because I want to 【详解】句意：我不使用一次性筷子。我想保护环境。前句是结果，后句是原因，题目要求用because合并，即引导原因状语从句，because是连词，后面需要接一个完整的句子；原句主语是I，want to do sth“想要做某事”。 62．如果这种意外发生，需要道歉。 If such an accident ________, apologies are needed. 【答案】occurs/happens 【详解】原句中“发生”是关键词，对应动词是happen或occur。这两个词均为不及物动词，没有被动语态，因此使用主动形式。主句“apologies are needed”使用的一般现在时的被动语态，表示一种常规规定或客观事实。在if引导的条件状语从句中，描述一般性真理或规定时，也应用一般现在时。从句的主语是“such an accident”（这种意外），属于第三人称单数，因此谓语动词需要加上-s，变为happens或occurs。所以填happens/occurs。 63．You learn the pioneers’ spirits. You will become more brave.（用if合并句子） You will become more brave ________ you learn the pioneers’ spirits. 【答案】if 【详解】句意：你学习先驱们的精神。你将会变得更加勇敢。前一句是实现后一句结果的条件，if意为“如果”，用于引导条件状语从句，符合语境。 64．You review your lessons every day. You won’t feel anxious in exams.（合并为一句） You won’t feel anxious in exams ________ you review your lessons every day. 【答案】if 【详解】句意：你每天复习你的功课。你考试时不会感到焦虑。可知前句“You review your lessons every day”是后句“You won’t feel anxious in exams”的条件，应用if引导条件状语从句，引出条件，表示“如果……”，因此if置于“You review your lessons every day”前，表示“如果你每天复习你的功课”，You首字母变为小写，时态为一般现在时，主句“You won’t feel anxious in exams”是一般将来时，符合条件状语从句“主将从现”的时态搭配规则。故填if。 65．You take advantage of learning resources. You will make fast progress. (用if合并句子) You will make fast progress ________ you take advantage of learning resources. 【答案】if 【详解】句意：你充分利用学习资源。你将会取得快速的进步。本题用if合并两个简单句，前句“You take advantage of learning resources.”是条件，后句“You will make fast progress.”是结果。空处需填if“如果”，引导条件状语从句。 66．如果你必须改变计划，提前让你的朋友知道。 If you have to ________ your plan, let your friends know ________ ________ ________. 【答案】 change ahead of time 【详解】原句中“改变”和“提前”是关键词，“改变”对应的英文单词为change，have to后接动词原形；表示“提前”的固定短语是ahead of time，故填change；ahead；of；time。 67．He was ill. He didn’t go to school. (合并为含 because 的复合句) He didn’t go to school ________ ________ ________ ill. 【答案】 because he was 【详解】句意：他病了。他没去上学。合并为含because的复合句，即because连接原因状语从句，主句是一般过去时，从句也是一般过去时，“because”后接从句“he was ill.”。故填because；he；was。 68．If you don’t work hard, you will fall behind. (改为同义句，用unless) ________ you work hard, you will fall behind. 【答案】Unless 【详解】句意：如果你不努力学习，你就会落后。改为同义句，if…not可以和unless进行转换，unless意为“除非，如果不”，其后接肯定形式。 69．Unless you keep trying, you won’t achieve your dream. (改为同义句，用if...not) ________ you ________ ________ trying, you won’t achieve your dream. 【答案】 If don’t keep 【详解】句意：除非你不断努力，否则你无法实现你的梦想。原句中“Unless”意为“除非”，相当于“if...not”（如果不）。本句主句为一般将来时，根据“主将从现”原则，从句应用一般现在时。将“Unless you keep trying”转换为“if”引导的否定句，即“If you don’t keep trying”。 70．他认为如果尽最大努力，就可以做好任何事情。 He thinks that he can ______________ if he ______________________________. 【答案】 do anything well tries his best 【详解】原句中“做好任何事情”为关键词，表示“做好任何事情”的英文短语为“do anything well”，情态动词can后面用动词原形。“尽最大努力”为关键词，表示“尽最大努力”的英文短语为“try one’s best”，主语“he”为第三人称单数，此处为if引导的条件状语从句，根据“主情从现”原则（主句含情态动词can，从句用一般现在时），第二空应填“tries his best”。 试卷第1页，共3页 试卷第1页，共3页 学科网（北京）股份有限公司 $