虚拟语气：1.I ___ the party much more if there hadn't been quite such a crowd of people there.A. would enjoyB. will have enjoyedC. would have enjoyedD. will be enjoying解析：答案应该是C。
因为if 从句是had +过去分词，是过去情况的虚拟条件句，主句应该用would have +过去分词。
2. Jean doesn't want to work right away because she tinks that if she ___a job, she probably wouldn't be able to see her friends very often.A. has to getB. were to getC. had gotD. could have got解析：if后面的句子是虚拟语气，根据句意，Jean现在不想工作，如果她有了工作，就不能经常见到她的朋友了，从句是表示对将来事实的假设，所以应该用表示将来的虚拟形式：were to do sth/should do/did。
3. _______ , he would not have recovered so quickly.A. Hadn't he been taken good care ofB. Had he not been taken good care ofC. Had not he been taken good care ofD. Had he been not taken good care of解析：虚拟条件句if可以省略，但从句的语序要用到装，即将were,had或should移至主语的前面形成倒装，但否定词not 不前移4.Had Paul received six more votes in the last election, he _________ our chairman now.A. must have beenB. would have beenC. wereD. would be解析：混合型的虚拟语气，主句和从句时间不一致；这时，主句和从句动词要根据各自所表示的时间进行调整。
5. The young driver looked over the engine carefully lest it ______ on the way.A. goes wrongB. would go wrongC. went wrongD. should go wrong解析：在lest, for fear that, in case, so that引导的副词从句中，谓语多用“should+动词原型”，should可以省略，意为“以防，生怕，唯恐”6.We could ______ him with a detached house when he came, but he had specifically asked for a small flat.A. provideB. have providedC. not provideD. not have provided 解析：前一分句一般表示过去没有完成的某个动作，是对过去情况的假设，谓语动词多用could/would have done形式；而后一分句是客观事实，可以根据情况使用一般过去时，过去完成时，或现在完成时。
7.Look at the terrible situation I am in! If only I ______ your advice.A. followB. had followedC. would followD. have followed解析：假设现在，if only 用一般过去；假设过去，had +动词过去分词或could have+过去分词；假设将来，would+动词原型；8.That tree looked as if it _____ for a long time.A. hasn't wateredB. didn't waterC.hadn't been wateredD. wasn't watered解析：as though，as if 引导的虚拟语气假设现在，一般过去；假设过去，had+v-ed; 假设将来，would/should+动词原型9.But for his courage, the battle ______ .A. was lostB. will be lostC. would loseD. would have been lost 解析：but for 多出现在句首，后面句子中的谓语动词可以是would/could+动词原型，也可以是would/could have+动词过去分词。
10.The traffic was very heavy; otherwise I ____ here 50 minutes sooner.A. would beB. should beC. had beenD. would have been11.A safety analysis _____ the target as potential danger. Unfortuately, it was never done.A. would identifyB. will identifyC. would have identifiedD. will have identified解析：“一次安全隐患分析本来会确认这个目标是潜在的危险。
不幸的是，这样的分析从未做过。
”这是对过去时间的虚拟，表示过去要做而没有做的事。
因而答案选 C. would have identified11.One of the requirements for a fire is that the material ____ to its burning temperature.A. is heatedB. be heatedC. will be heatedD. would be heated解析：require that +（should）do：要求……，其中should可以省略。
再加上被动语态，所以应该是be heated.12.If you have really been studying English for so long, it's about time you _____ to write letters in English.A. should beB. wereC. must beD. are解析：It is （high/about）time +that 从句，从句的谓语需用一般过去式或should +动词原形（should不可省略）13.That was not the first time he ______ us. I think it's high time we ______ strong actions against him.A. betrayed, takeB. had betrayed, tookC. has betrayed, tookD. has betrayed, take解析：this / that was the 序数词time + 句子（谓语动词是过去完成时），第一空应填had betrayed；It is （high/about）time +that 从句，从句的谓语需用一般过去式或should +动词原形（should不可省略）Exercises1. It is essential that the application forms _____ back before the deadline.A. must be sentB. would be sentC. be sentD. were sent解析：主语从句，It was essential that +虚拟语气（should do，should可以省略）2. If the earth ____ spinning, we would all fly off it.A. had stoppedB. stoppedC. has stoppedD. would stop解析：主句would+动词原型表示对现在的虚拟，从句用过去式。
3. ____ for my illness I would have lent him a helping hand.A. Not beingB. Had it not beenC. Without beingD. Not having been解析：虚拟条件句if可以省略，但从句的语序要用到装，即将were,had或should移至主语的前面形成倒装，但否定词not 不前移4. To be frank, I'd rather you _____ in the case.A. will not be involvedB. not involvedC. not to be involvedD. were not involved解析：固定搭配，would rather sb. did...5. We didn't know his telephone number, otherwise we ______ him.A. would have telephonedB. must have telephonedC. would telephoneD. had telephoned6. _____ before we depart the day after tomorrow, we should have a wonderful dinner party.A. Had they arrivedB. Would they arriveC. Were they arrivingD. Were they to arrive解析：虚拟条件句if可以省略，但从句的语序要用到装，即将were,had或should移至主语的前面形成倒装，但否定词not 不前移。
而且从句表示对将来的虚拟，因此用Were to.7. If only the committee _____ the regulations and put them into effect as soon as possible.A. approveB. will approveC. can approveD. would approve解析：if only ：对过去虚拟，用完成时态。