虚拟语气在if条件从句中的用法在if引导的虚拟条件句中，若表示与现在事实相反，从句谓语用动词过去式(be的过去式用were )，主句谓语用 “would(should, could, might)+have+过去分词”；若表示与将来事实 相反，从句谓语用动词过去式(were to +动词原形，should+动词原形)”，主句谓语用“would(should, could, might)+动词原形”。若把从句中 were, should或had移到句首，可省略从句的连词if并使用倒装语序. If my lawyerhere last Saturday ,heme from going.(NMET 89)A. had bee n ;would have preve ntedB. had bee n ; would preve ntC. were ;would preve ntD. were;would have preve nted -If he,hethat food.-Luckily he was sent to the hospital immediately.(MET 93)A. was warned ;would not takeB. had bee n warned ;would not have take nC. would be warn ed; had not take nD. would have bee n warn ed; had not take n I didn t see your sister at the meetingf she,she would have met mybrother.(NMET 94)A. has come B. did come C. came D. had come it rain tomorrow, we would have to put off the visit to the Yangpu Bridge.(1994,上海)A. Were B. should C. Would D. Will2 考查通过上下文或介词短语表示虚拟条件的虚拟语气的用法在英语中，有时假设的条件不是通过if条件句表达出来，而是通过上下文或without, but for等介词构成的短语表达，其谓形式要根据所假设的时间，与if从句所表达的时间对应，确定主句谓语形式。考例Without electricity human lifequite different today.(NMET 91)A. is B. will be C. would have bee n D. would beI told Sally how to get here ,but perhaps Ifor her .(NMET 94)A. had to write out B. must have written it outC. should have written it out D. ought to write it outwithout the air to hold some of the sun s heat, the earth at night, too coldfor us to live.(1997, 上海)A. would be freez ing cold B. will be freez ing coldlyC. would be froze n cold D. can freeze coldly3. 考查虚拟语气在 as if 引导的方式状语或表语从句中的用法As if引导的方式状语或表语从句，谓语动词用“一般过去式”表示与现在事实相反；用would(might, could)+动词原形”表示与将来事实相反。The two strangers talked as if theyfriends for years.(1993,上海 )A.shouldbe B.would be C.have bee n D.had bee nWhen a pencil is partly in a glass of water, it looks as if it.(NMET 95)A.breaks B.has broke n C.were broke n D.had bee n broke n4. 考查虚拟语气在 wish后面宾语从句的用法Wish后面的从句，谓语用“过去式”表示现在不能实现的愿望；用“had+过去分词”表示过去没有实现的愿望；用“ would(should,could) +动词原形”表示将来不能实现的愿望。考例 I wish Iyou yesterday.(Met ” 88)A. seen B.did see C.had seen D.were to see5 考查虚拟语气用于宾语从句的用法。在及物动词in sist ,order ,require ,dema nd, comma nd等后面，宾语从句所说的是尚未发生的事，所以谓语要用与将来事实相反的虚拟语气，即“should+动词原形”表达。其中should可以省略。考例(11) The guard at the gate insisted that every bodythe rules.(MET 85)A. obeys B. obey C. will obey D. would obeyA. take B. taken c. took D. will take答案:1-5 ABDBD 6-10 CADCC 11-12 BA1. Elize remembers everything exactly as if ityesterday.（2006全国卷一 ）A. was happe ning B .happe ns C. has happe ned D. happe ned解析:D.考察虚拟语气.as if引导的从句通常用虚拟语气.又因remember知 与现在事实相反，因此用一般过去时.2. fired, your health care and other ben efitswill not be immediately cut off.（2006湖北）A. would you be B. should you beC. could you be D. might you be解析:B考察虚拟语气的倒装.if引导的条件状语从句，如果用虚拟语气，可以把if省略,将助动词 were, had 或should 提前，构成倒装.3. I was on the highway when this car went past followed by a police car. Theyatleast 150 kilometers an hour.（2005重庆）A. should have bee n doing B. must have bee n doingC. could have done D. would have done解析:B考察虚拟语气.表推测4. He paid for a seat, when hehave entered free.（2005山东）A. could B. would C. must D. n eed解析：A.考察虚拟语气情态动词的用法5. Mr.Whit eat 8:10 for the meeting, but he didn t show up.（2004全国卷三）A. should have arrived B. should arriveC. should have had arrived D. should be arrivi ng解析：A本题考察虚拟语气及责备的用法.Should have done结构,表过去原本该做而没做的事高考预测：1. What would have happe ned if youher child ?A.hadn t helpedB. couldn t help C. wouldn t help D. didn t help解析：A表示过去时间的虚拟是条件从句，用过去完成时，主句用would (should)+have +动词原形。2. If Iwith her last summer, Iwith her now .A. worked -am getting on very wellB. had worked -will get on very wellC. had worked -would have got on very wellD. have worked -will get on very well.解析：B。本题是混合式虚拟语气。主句是对现在时间的虚拟。3. The boss ordered that hethe work at onceA. starts B. will start C. would start D. start解析：D order, suggest等词后的宾语从句，要用虚拟语气，构成为 should +v, should可以省略。4. The little hero s pale face suggested hedead.A. is B. was C. should be D. be解析；B不作建议讲时，宾语从句谓语不用虚拟语气。5. I known it, I should have told him .A. have B. had C. havi ng D. Ifhad ,should解析：B这是一个与过去事实相反的虚拟语气，如非真实性条件句谓语含 were时，可将这些词提到句首，省去if.6f you had gone to a doctor, youall right now.A. would not come B. might not comeC. should not come D. could not come解析：C表示与将来事实相反的虚拟语气句。