高考英语二轮复习考点练习考点23条件、让步和原因状语从句 (含解析)

考点23 让步和原因状语从句 考向三、条件状语从句 1. if引导的条件状语从句 if可引导非真实条件状语从句(见＂虚拟语气＂)和真实条件状语从句。 If he said that, he can’t be telling the truth. 如果他说了那样的话，他不可能是说实话。 2. unless引导的条件状语从句 unless引导的是否定条件状语从句，在意义上相当于if...not，而且语气较强，一般不用于虚拟语气。 You’ll be late unless you hurry. 你会迟到的，如果不赶快的话。 1.（2019·江苏卷·单项填空）The doctor shares his phone number with the patients __________ they need medical assistance. A. if only B. as if C. even though D. in case 【答案】D 【解析】考查状语从句的连词。句意：医生给了病人他的手机号码，以防病人需要医疗援助。A. if only要是……多好；B. as if好像，仿佛；C. even though即使，尽管；D. in case以备，以防，免得，引导条件状语从句。故选D。 2.（2019·天津卷·单项填空）Tom is so independent that he never asks his parents' opinion _________ he wants their support. A. since B. once C. unless D. after 【答案】C 【解析】考查连词辨析。句意：汤姆是如此独立，以至于他从来不征求父母的意见，除非他想得到他们的支持。since因为；once一旦；unless除非；after在……之后，根据题意，故选C。unless在此引导条件状语从句。 3.(2018·北京卷·单项填空) _________ we don’t stop climate change, many animals and plants in the world will be gone. A. Although B. While C. If D. Until 【答案】C 【解析】考查状语从句。句意：如果我们不阻止气候变化，那么世界上的很多动植物将会消失。分析句意及句子结构可知，动植物不灭绝的前提条件是阻止气候变化。although尽管；while当……时候，尽管；if如果；until直到。根据句意可知选C。 4.________ we have enough evidence, we can't win the case. A. Once B. As long as C. Unless D. Since 【答案】C　 【解析】考查连词。句意：如果我们没有足够的证据，我们就赢不了官司。后句说官司打不赢，用unless来表示相反的条件。 【名师点睛】条件状语从句就是在复合句中表示主句动作发生条件的状语从句。引导条件状语从句最经常用的连词是if，它的意思是＂如果＂； 也可以用unless引导：unless的意思是＂如果不＂＂除非＂，相当于if not。 3. only if引导的条件状语从句 only if在引导条件状语从句时意为＂只有……(才)；只有在……的时候，唯一的条件是……＂。 I’ll let you use the car only if you keep it in good condition. 只要你把车保养好，我就让你用。 4. as/so long as引导的条件状语从句 as/so long as意为＂只要；如果＂。 As long as it doesn’t rain, we can play. 只要不下雨我们就能玩。 You won’t find paper cutting difficult _____you keep practicing it. A. even if B. as long as C .as if D. ever since 【答案】B 【解析】句意：只要你不断练习，你不会觉得剪纸很难。A. even though即使，虽然;B. as long as只要；C. as if犹如，好像；D. ever since自从。结合句意，此处用as long as引导条件状语从句。故选B。 5. provided (that)/providing (that)引导的条件状语从句 provided (that)/providing (that)意为＂假如；如果＂。 I will agree to go provided / providing (that) my expense is paid. 假如为我负担费用，我就同意去。 Providing you promise not to tell anyone else I’ll explain the secret. 假如你承诺不告诉别人，我就告诉你这个秘密。 6. on condition that（条件是）和suppose / supposing (that)（假设；如果）也可引导条件状语从句 I can tell you the truth on condition that you promise to keep it a secret. 我可以告诉你真相，条件是你答应保守秘密。 Suppose/ Supposing (that) they refuse us, who else can we turn to for help? 在条件状语从句中，通常要用一般现在时表示将来意义，而不能直接使用将来时态。不过，有时表示条件的 if之后可能用 will，但那不是将来时态, 而是表示意愿或委婉的请求(will为情态动词)。 If you will sit down for a few moments, I’ll tell the manager you’re here. 请稍坐片刻，我这就通知经理说您来了。 考向四 让步状语从句 让步状语从句是状语从句中的一种。 一般翻译为＂尽管……即使……＂就是我们日常生活中用的＂退一步说……＂的感觉。 引导让步状语从句的连词主要有以下这些：though, although, as; even if, even though; whether...or...; no matter+疑问词，疑问词-ever。下面对这些连词引导的让步状语从句作一说明。 1. although/though引导的让步状语从句 although和though，都作＂虽然；尽管＂解，通常可以换用，although的语气较重。如果要强调＂但是＂语气，可使用yet，still或nevertheless来表示＂但是＂、＂依然＂或＂然而＂之意。 Although they have been talking for a long time, he cannot make her believe him. 虽然和她谈了半天，他还是不能让她信任自己。 We had to wait half an hour ________we had already booked a table. 　A. since B. although C. until D. before 【参考答案】B 【答案解析】句意：尽管我们已经预定了桌子，但还是等了半小时。分析句子结构可知，此处是让步状语从句，所给四个选项中只有although可以引导让步状语从句。故选B。 2. even if/even though引导的让步状语从句 （1）even if引导的让步状语从句 even if ＂即使，纵然＂，从句表示的是尚未发生的动作或存在的情况。 Even if it rains tomorrow, we won’t change our plan. 即使明天下雨，我们也决不改变计划。 Even if I failed again, I will not give up the experiment. 即使我再次失败，我也决不会放弃实验。 （2） even though引导的让步状语从句 even though＂虽然，尽管＂，从句所表示的是已经发生的动作或存在的情况，通常可以和although/though换用。 Even though I didn’t understand a word, I kept smiling. 即使我一个字也不懂，我还是保持微笑。 Even though you say so, I do not believe it. 即使你这样说，我也不信。 （2016·北京卷﹒单项填空）My grandfather still plays tennis now and then, _______________ he’s in his nineties. A. as long as B. as if C. even though D. in case 【参考答案】C 【答案解析】考查状语从句。句意：即使九十多岁了，我的爷爷仍然时不时地打打网球。A.as long as只要，引导条件状语从句；B.as if似乎，引导方式状语从句或表语从句；C. even though即使，引导让步状语从句；D.in case以防，引导目的状语从句。这里是转折关系，故选C。 3. as引导的让步状语从句 as引导让步状语从句时，意为＂尽管，虽然＂，从句多位于主句之前，而且必须使用倒装语序。通常如果从句中有形容词或名词作表语，则把表语置于句首，而且名词前要省略冠词；如果从句中有修饰动词的副词，则将该副词置于句首；如果从句中有情态动词，则将情态动词后的动词原形置于句首。此用法与though的倒装完全一致。(although无此用法) Much as I admire his courage, I don’t think he acted wisely. 我虽然佩服他的勇气，但我认为他这样做是不聪明的。 Strong as you maybe, you cannot lift it. 虽然你可能很有力气，你却无法把它提起来。 Child as he is, he is very brave.尽管他还是个孩子，但是他很勇敢。 1._________， his idea was accepted by all the people at the meeting. 　A. Strange as might it sound 　B. As it might sound strange 　C. As strange it might sound 　D. Strange as it might sound 2._________， Carolina couldn’t get the door open. 　A. Try as she might B. As she might try 　C. She might as try D. Might she as try 【参考答案】1.D 2.A 【答案解析】分析句子结构可知，以上两题都是有as引导的让步状语从句，因此要要倒装语序。 4. while引导的让步状语从句 while＂虽然，尽管＂，多用于正式文体，且多位于句首，相当于although。 While I understa