一、表示惊异、遗憾、不满等语气。

　　1.与疑问词how, why等连用，有"竟、会"之意。例如：

　　①Why should you stand there like a fool?你怎么像傻子一样站在那里？

　　(should+do表示现在的情况。)

　　②How should I know? Has it anything to do with me?我怎么知道？这和我有什么关系？

　　③I don't know why you should have told him that much.我不明白你为什么跟他说那么多。

　　(should+have done表示已发生的情况。)

　　2.在It's surprising/ strange/ a pity...以及I'm surprised/ sorry...等句型中，当"竟然会"讲。例如：

　　①It's surprising that you should be so foolish.真令人吃惊，你竟会如此愚蠢！(现在)

　　②It's surprising that you should have failed to pass such an exam.真令人吃惊，这样的考试你竟然不及格。(已发生)

　　3.单独用"should (not) +have+过去分词"形式，对已发生的事表示遗憾或责备，表达"本该或不该"之意。例如：

　　①He also learns that he should have cared more about his friends.他还明白了他本应该多关心朋友。(高一课本上册P4)

　　②He shouldn't have let out the secret.他本不该泄露秘密的。(实际情况是"他已泄密"。)

　　二、用于揣测，表示可能或期望，意思是"照理说来、应该"。

　　在语气上should比must弱，但比may/ might强；shouldn't比

　　can't弱，但强于may/ might not。例如：

　　①I should be home in about ten minutes.照理说来，约十分钟后我就能到家。(高一课本上册P59)

　　②He should be having class now.他现在应该是在上课。

　　③As far as I know you shouldn't have any problems there.就我所知，在那里你不会遇到任何问题。

　　④According to the schedule, they should have arrived in Shanghai by now/ yesterday.按照计划，他们现在/昨天应该已经到达上海了吧。

　　(注：本句中的"should+have done"结构并不表示责备，仅表示说话人的揣测。)

　　三、表示建议和要求，当"应该"讲。

　　1.表示说话人的意向。例如：

　　①I think a friend should be kind.我认为朋友应该是善良的。(高一课本上册P1)

　　②You should not go rafting unless you know how to swim, and you should always wear a life jacket.如果不会游泳，你就不能去漂流；而且(漂流时)应该穿救生衣。(高一课本上册P18)

　　③Should the naughty boy be punished?那个调皮的男孩该受惩罚吗？

　　④It's necessary/ important/ natural that we should do it again.我们应该重做。

　　2.在与某些表示"建议和要求"的动词或名词搭配的从句中，用"should+动词原形"的形式，表示"建议或要求做某事"，should可以省略。这类词常用的有：suggest(建议)/ suggestion, require, request, insist(坚持)等。例如：

　　①They suggested that Ed (should) start at 8 a.m..(宾语从句)

　　②It was suggested that Ed (should) start at 8 a.m..(主语从句)

　　③Ed received their suggestion that he (should) start at 8 a.m..(同位语从句)

　　④Their suggestion was that Ed (should) start at 8 a.m..(表语从句)

　　上述四个句子中的从句都表示建议的内容"Ed应该早八点出发"。

　　四、表示假设。

　　1.在虚拟条件句中用以加强假设语气，用"should+do"指将来的情况，当"万一(会)"讲。例如：

　　①If it should rain (=Should it rain) tomorrow, I should/ would stay at home.万一明天下雨的话，我就待在家里。

　　②Please call me if (=in case) you should need my help.万一需要我帮助的话，请给我打电话。(此句中should need可用need代替。)

　　2.在虚拟语气的主句中表示假设的结果，当"就会"讲。("should+do"表示现在或将来时间；"should+have done"表示过去或到目前为止的时间。)例如：

　　①If he were here, I should tell him the truth.如果他(现在)在这里的话，我就会告诉他真相。(事实是，他现在不在这里。)

　　②If I had been here yesterday, I should have taught him a good lesson.如果昨天我在这里，我就会好好教训他一顿。(事实是：我没教训他，因为我昨天没在这里。)

　　③I shouldn't have won without your help.如果没有你的帮助，我就赢不了。(事实是我已经获胜。)

　　另外，should还可以用于目的状语从句中，用法类似于假设语气，当"就会"讲。例如：

　　I turned down the radio so that it shouldn't wake the baby up.为不惊醒婴儿，我把收音机音量调小。

　　五、表示委婉语气。(用于第一人称)例如：

　　①I should say you are wrong.我得说你错了。

　　②I should like to have a look at your new stamp.我想看看你的新邮票。

　　六、指纯粹过去将来。例如：

　　I said I should come early.我说过我会早来。(其直接引语是："I shall come early," I said.)

　　请看下列与should有关的高考试题：

　　解题技巧提示：正确解题的关键在于正确理解语言环境，把握说话人的语气和句子中的时间信息从而正确理解句子含义。

　　1.I was really anxious about you. You _______ home without a word.(NMET 2001)

　　A.mustn't leaveB.shouldn't have left

　　C.needn't leaveD.couldn't have left

　　2.I'm not feeling well in the stomach, I _______ so much fried chicken just now.(2002,上海)

　　A.shouldn't eat

　　B.mustn't have eaten

　　C.mustn't eat

　　D.shouldn't have eaten

　　3.We _______ last night, but we went to the concert instead.(NMET 1992)

　　A.must have studied

　　B.might study

　　C.should have studied

　　D.would study

　　4.I told Sally how to get here, but perhaps I _______ it out for her.(NMET 1994)

　　A.had to write

　　B.must have written

　　C.should have written

　　D.ought to write

　　5.That young man has made so much noise that he _______ not have been allowed to attend the concert.(1992，上海)

　　A.couldB.mustC.wouldD.should

　　6.It's nearly seven o'clock. Jack _______ be here at any moment.(NMET 1995)

　　A.must B.need C.shouldD.can

　　7.-When can I come for the photos? I need them tomorrow afternoon.

　　-They _______ be ready by 12:00.(NMET1998)

　　A.can B.shouldC.mightD.need

　　8.Mary _______ be in Paris, for I saw her in the town a few minutes ago.(NMET 1994)

　　A.mustn'tB.can't

　　C.shouldn'tD.may not

　　9.I didn't see her in the meeting room this morning. She _______ have spoken at the meeting.(MET 1991)

　　A.mustn'tB.shouldn't

　　C.needn'tD.couldn't

　　10.-There were already five people in the car，but they managed to take me as well.

　　-It _______ a comfortable journey.(NMET 1995)

　　A.can't beB.mustn't have been

　　C.shouldn'tD.couldn't have been

　　11.If only he _______ quietly as the doctor instructed, he would not suffer so much now.(2000，上海)

　　A.liesB.lay

　　C.had lainD.should lie

　　12.It's hard for me to imagine what I would be doing today if I _______ in love, at the age of seven, with the Melinda Cox Library in my hometown.(2002，上海)

　　A.wouldn't have fallen

　　B.had not fallen

　　C.should fall

　　D.were to fall

　　13.Johnny, you _______ play with the knife, you _______ hurt yourself.(NMET 1996)

　　A.won't; can'tB.mustn't; may

　　C.shouldn't; mustD.can't; shouldn't

　　14.-Are you coming to Jeff's party?

　　-I'm not sure. I _______ go to the concert instead.(NMET 2000)

　　A.mustB.wouldC.shouldD.might

　　15.A left-luggage office is a place where bags _______ be left for a short time, especially at a railway station.(NMET 2003)

　　A.shouldB.canC.mustD.will

　　16.When Ed first phoned and _______ we play, I laughed quietly, figuring on an easy victory.(NMET 2003)

　　A.declared B.mentioned

　　C.persuadedD.suggested

　　参考答案：

　　1-5题都是对已发生的事表示遗憾和责备，须用"should+have done"的形式。答案分别为BDCCD。

　　6-10题考查情态动词表示推测的功能。第6、7题考查对将来情况的推测，用should表示"照理应该、照理会"的意思，答案分别为C和B。第8题考查对现在情况的推测，句子背景提示我们"几分钟之前我刚在小镇中见过她"，因此"她现在不可能在巴黎"，考虑到动词的语气，应选B。第9、10两题考查对过去情况的推测，具体的语言环境分别暗示"她不可能在会议上发言"和"那不可能是一次令人舒适的旅行"，should表示的语气较弱，不能表达"不可能"的意思，应该用can't或couldn't，故答案分别为D和D。

　　11-12题考查动词的虚拟语气。在假设条件句中，"should+do"只能表示现在或将来的情况，而两题都指已发生的情况，须用过去完成形式，故答案分别为C和B。

　　13-14题考查对说话人的要求和意向的理解。受语境影响，答案分别为B和D。

　　15题选项中的should显然不符合句子背景。行李"可以"暂放行李寄存处，而非"应该"。故答案应为B。

　　16题选项及题干中虽未出现should，但句子时态已给我们足够的暗示，主句谓语为过去时，而宾语从句中却用动词原形，四个选项中只有D项适合此种用法，表示"建议做某事"，动词play前实际上是省略了情态动词should。

　　(文/山东青州二中时永春；英语通高中一年级版03～04学年第2期；版权归英语辅导报社所有，独家网络合作伙伴新浪教育，未经许可，不得以任何形式进行转载。)