1.You should have put the milk in the icebox; I expect it _____ undrinkable by now.a.becameb.has becomec.had becomed.becomes2.If you smoke in a non-smoking section,people _____ .a.have objectedb.objectedc.must objectd.will object3.I decided to go to library as soon as I _____ .a.finish what I didb.finished what I didc.would finish what I was doingd.finished what I was doing4.Before the first non-stop flight made in 1949,it _____ necessary for all planes to land for refueling.a.would beb.has beenc.had beend.would have been5.There was a knock at the door.It was the second time someone _____ me that evening.a.had interruptedb.would have interruptedc.to have interruptedd.to interrupt6.We _____ to start our own business,but we never had enough money.a.have hopedb.would hopec.had hopedd.should hope7.In this experiment,they are wakened several times during the night,and asked to report waht they ______.a.had just been dreamingb.have just been dreamingc.are just dreamingd.had just dreamt8.The second book was _______ by August 1952,but two years later,the end was still nowhere in sight.a.completedb.to have completedc.to completed.to have been completed 1.b现在完成时用法。牛奶变质发生在“过去”时间，但本句所要着重说明的是“现在”牛奶不能喝了。2.d一般将来时用法。显然，从句和主句谓语动词所发生的时间都是将来，因而主句用一般将来时。注意，在时间，条件状语从句中，用一般现在时表示将来时。egI''ll ring you up as soon as I get an answer from him.3.d过去一般时的用法。根据题意，as soon as 所引导的时间状语从句中，谓语动词finish所发生的时间为“过去将来”。这里的“过去将来”要用一般过去时来表示，不用过去将来时，所以用d.egThey had to leave early as they started work the next day.4.c测试过去完成时，题句中从句谓语动词所表示的动作发生在1949年，主句谓语动词所表示的情况发生在此之前，所以用过去完成时。5.a此时过去完成时。在“It was the first time (that)------”这样的结构中，that分句中的谓语动词通常用完成时。egIt was the third time he had been in love that year.6.c测试过去完成时。expect,hope,intend,mean,suppose,think,want等动词的过去完成时可以表示未能实现的希望，愿望，打算等。egI had hoped to send him a telegram to congratulate him on his marriage,but I didn't manage it.7.b测试现在完成进行时。现在完成进行时可用来表示一个动作从过去某时开始，一直延续到说话时刻，在说话时，这个动作刚刚结束。现在完成进行时往往强调动作的持续性。题中dream着一动作，从被要求报告之前的过去某时开始，一直延续进行到被叫醒要求报告时为止，由于被要求报告的是梦的过程，即强调动作的持续性。所以B。egI 've been writing letters all this morning.8.d测试was/were+动词不定式完成式。was/were+动词不定式完成式表示本打算完成而实际上未完成。egI was to have started work last week,but I changed my mink.