高中英语核心语法点汇编 part 17 助动词与情态动词用法释疑 清单-2026届高三英语一轮复习专项

高中英语核心语法点汇编 part 17 助动词与情态动词用法释疑 1 情态动词可否属于助动词？ 有读者问： 初中英语书中提到“情态动词”，但有时则将 may 与 need 都标作助动词。我的理解是“情态动词”也可属于“助动词”，不知正确否？ 是的，“情态动词”可以单独作为一类动词；但也可以将它隶属于助动词，唤作“情态助动词”，而另一类助动词可唤作“基本助动词”或“时态助动词”。 2 这里的did和didn't不可改为would和wouldn't 有读者问到这样一段对话： — Jenny never thought she would be late again, did she? — No, she didn't. Because her father was very strict with her. 我认为对话中的did和didn't应改为would和wouldn't,不知对否？ 不对，这里应用did和didn't。只有在“单数第一人称I+think, believe, suppose等动词+宾语从句”结构中，其中的附加疑问句的主、谓语方可与宾语从句的主、谓语一致。 3 直接引语中的shall在间接引语中只应用would吗？ 有读者问： Quirk等著的《英语语法大全》与Alexander著的《朗文英语语法》都说，在直接引语中shall表示预测将来时，变间接引语时应用would。但： (1)We shall have an English text next week. 是否可转述为： (2)The teacher said that we should have an English text the next week. 上述《英语语法大全》和《朗文英语语法》有关直接引语中表示预测将来的shall变为间接引语时应用would的论述，有点语焉不详，过于简略。他们所举的应用would的间接引语的主语都是第三人称，无一主语是第一人称。例如《朗文英语语法》所给的间接引语的主语就只有第三人称： (3)“I shall tell him exactly what I think,” she said. （直接引语用shall） (4)She said she would tell him exactly what she thought. （间接引语用would） 我们觉得，据此似乎还不能得出这样的结论： 直接引语中的表预测将来的shall变成间接引语时，只可用would，不可用should。我们翻阅了几本较为可靠的近年出版的辞书，差不多都有间接引语中主语I/we可用should的例证，如： (5)She banged on the door and said we should be late. (6)Did the doctor say I should recover soon. (7)I estimated that I should finish in ten days. (8)I thought I should never see you again. (9)I told you I should not be in for dinner. 因此，我们认为A.J.Thomson和A.V.Martinet合编的A Practical English Grammer （Oxford University Press)的提法较为稳妥。该书说： 直接引语变为间接引语时，I/we shall可变为I/we should或I/we would，但would较为普通（大意如此，见该书第293节末尾）。顺便提一下，I/we would之所以压倒了I/we should，正如I/we will压倒了I/we shall一样，都是受了美国英语的影响的缘故。 基于上述分析，你所举的上述句（2）自然是正确的，但在当代英语中，更不必说美语，将should代之以would恐已是大势所趋了。 4 shall在此的意味 有读者问： 有这样一句话： (1)Should the named vessel arrive earlier than the date of arrival as previously notified to the sellers, the buyer shall advise the sellers in time. 这里的shall意味着什么？ 句中的shall，是常用在契约、章程等中表“必须”的一个情态动词，再如： (2)The seller shall provide all necessary information for the maintenance of the machine. (3)The vendor shall maintain the equipment in good repair. 5 shall表命令和询问时亦可用于第三人称 有读者问： 有两道选择题： (1)Tell him that he_________come here immediately. A. shall B. will C. need D. would (2)_____ he open the door? A. Shall B. Will C. Can D. Would 答案都是A，我不知为什么。 上述句（1）之所以应选A，是因为表命令的shall亦可用于第三人称，再如： (3)He shall do it, whether he wants to or not. 上述句（2）之所以应选A，是因为表示征求对方意见的shall也可用于第三人称，再如： (4)What shall he do next? (5)Shall the messenger wait? 6 这里的 shall 有什么含义？ 有读者问： Who touches pitch shall be defiled. 这一句中的shall 有什么含义？ 这里的 shall 应看作情态动词，表示命运或必然结果，有时亦可表上帝的意旨。这种 shall 多用在很正式或古旧的英语中。再如： (1)Death is certain to all, all shall die. (2)Better days shall soon follow. (3)The time shall come when Egypt shall be avenged.（第一个 shall 表上帝的意旨。第二个 shall 则是虚拟式。） 7 should 可以表“可能”吗？ 有读者问：我们遇到这样一句话： (1)She should arrive directly. 有人说 should 在此不表“应该”而表“可能”，请问 should 可以表“可能”吗？ 情态动词 should 除可表“应该”外，也可表“可能”，意味着一种推测。你所举的例子中的 should 即表示“可能”。再如： (2)John should be at home. (3)John should be working. (4)John should have left by tomorrow. 但下面一句则可能有歧义： (5)He should have arrived yesterday. 这句话可能意谓“他可能昨天就到了”，也可能意谓“他本该昨天到的（但却没到）”。 顺便提及，上述例句中的 should 皆可被 ought to 所代替而意义不变。又 should 与 ought to 表“可能”时一般不可用于否定陈述句与肯定疑问句，以免与表“应该”的情况相混淆。但可用在否定疑问句中，如： (6)Shouldn't he be home now? 8 这里为何用shouldn't have received？ 有读者问： 有这样一句话： (1)Mary shouldn't have received my letter; otherwise she would have replied before now. 这里为什么不用couldn't have received而用shouldn't have received? should在此亦表“可能”，但不似could那么肯定。“should have+过去分词”表“可能”或“大概”的情况并不罕见，除上述句（1）外，再如： (2)John should have left by tomorrow. (3)Have you heard from Maria? She should have started her job on Monday. (4)Lest you should not have heard all, I shall begin at the beginning. 顺便说一下，“should have+过去分词”还可以表“竟然……”和“应该……”等，例如： (5)It is strange that he should have done it. (6)The task should have been completed before the meeting. 9 should和ought to的区别 有读者问： should和ought to的区别如何？ should和ought to都意为“应该”，但前者的语气较为委婉，亦较为普通，常用以表一般性的忠告或意见，如： (1)Carbon steel knives should be wiped clean after use. (2)Crimes should be punished. ought to的语气较强，常用以表示有针对性的意见，如： (3)We ought to tidy up before we go home. (4)She ought to see the doctor. 但ought to有时有“大概”的含义，如： (5)He ought to be home by now. 10 should与can皆表“可能”时的区别 有读者问： 有这样一道选择题： (1)— When can I come for photos? I need them tomorrow afternoon. — They_________be ready by 12:00. A. can B. should C. might D. need 答案是B，请问A为何不可？ 情态动词should在此表示“可能”，具有推定性，无十分把握，相当于汉语的“料想”，再如： (2)She should be here in a minute. (3)That should be easy. (4)Three weeks should suffice. (5)You should be able to learn to swim in three hours. 情态动词can表理论上“可能”，如： (6)Lightning can be dangerous. (7)He can sometimes be very nasty. 因此此处不宜用can。 11 should come, would come, will come都不错 有读者问： 有这样一道选择题： (1)I wish that she_________this afternoon. A. will come B. can come C. should come D. would come 我认为应选D，而答案给的是C，请问为什么？ 这道题似乎不够严谨。其答案可以是C，也可以是D。C的语气要比D强一些，should come和would come都是虚拟语气。在当代英语中，亦可用A，再如： (2)I wish that other people like me will cherish the same love for the motherland. 12 “should have+过去分词”不只有一种用法 有一读者来信说：我们的语法书上讲“should have+过去分词”都是用以表示过去应发生而未发生的事，如： (1)You should have seen the film. 但我遇到下面一段对话： (2)— Now, Nils, let us have a talk. — Can we have anything to talk about? — We have a great deal to talk about. — I shouldn't have thought so. 请问这里的 shouldn't have thought 是什么意思？ “should have+过去分词”除可表示过去应发生而却未发生的事之外，还可用以表示其他一些情况。你所举“I shouldn't have thought so.” 中的 shouldn't have thought 只是其中的一种情况。这种“should have+thought”已成为一种比较固定的说法，常用以表示非常谦逊委婉、语气不肯定（其程度还要胜过 should think）, 再如： (3)I should have thought you might control yourself. (4)I should have thought it rather unfair. 上述 should have thought 皆意谓“认为”，但有时则可意谓“本以为”或“本认为”（而这正是 should have thought 的本义）， 如： (5)— Can you eat any meats? — Certainly. — Funny. I should have thought you wouldn't.（这里的 should 常可被 would 所代替） 下面一句中的“should have+thought”是用在虚拟语气中： (6)I should have thought my work half completed had I made it a mere register of verbal distinctions. 再如： (7)If ever she should have hated Basil, it was now. 下面句子中的 should 则表“可能”： (8)I think it should have worked by this time. 下面一句中的 should 则与 why 连用： (9)Why should that have been enough? 13 will可表“意愿”或“请求” 有读者问： 有一道选择题： (1)If you_________quiet, I'll tell you what happened. A. are B. will be C. care to be D. be 答案为B，但语法上不是说用一般现在时表将来吗？ 为什么不选A呢？ 根据题意，这里应有“肯静下来”的含义，而will be quiet正是这个意思，故而应选B。A无“肯”或“愿意”之义，故而不能入选。关于if you will...再举一二例如下： (2)I'll thank you if you will give me a hand. (3)I'll be glad if you will come. 其实上述will都有“请求”的含义。有时则可只用if从句，如： (4)Now if you will step this way. 14 在此will≠将要 有读者问： 小说《简·爱》（Jane Eyre ）第19章有这样一句话： (1)Fetch me, now, Jane, a glass of wine from the dining-room; they will be at supper there; ... 有一译本将they will be at supper there译作“他们将在那里吃晚饭”。但另一译本则译作“他们大概在那儿进晚餐”。孰对孰错，请指教。 前一译本显然错了，后一译本对了。为什么这样说呢？ 理由有二： 一是will除常表将来外，亦可表现在。它表现在时是一情态动词，表示推测或很可能，相当于汉语的“必定”或“我料想”。如： (2)This will be the book you're looking for. (3)That will be Roland: I can hear him at the door. 有时可与表现在的时间词now，by this time等连用，如： (4)It will be raining now in Shanghai. (5)They will be home by this time. 二是可从下文看得出来。下文是：I went. I found all the party in the dining-room at supper, ... 15 这里的 would 有什么含义？ 有读者问这样一句话： When the deals were about to be completed, people dressed as police would appear to confiscate all the money. 请问这里为什么用 would? 这里的 would 表过去习惯，说明类似的事不断发生，全句可译为：每逢这些交易即将完结，穿警服的人员就会出现并没收全部钱款。 16 这个句子有什么错？ 有读者问这个句子有什么错？ (1)Why was it that a well-educated, attractive English girl would turn her back to glittering social life in order to be a nurse when only women of low class and reputation worked in hospitals? 此句错在用了 would。在英语中，疑问词 why, how等的语气较为强烈时，其后应用 should。上述句子用的是“Why was it that...”强调结构，表明 why 的语气十分强烈，故而须将 would 改作 should。语气强烈的 why, how 等疑问词与 should 连用的日常用语有如： (2)Why should I go? (3)How should I know? 17 用不用should皆可 有读者问： 最近在做TOEFL练习中，遇到这样一句话： She insisted that they should give her a receipt. 书上说这是一个错句，正确句应去掉should。但我的语法书说用不用should都可以。究竟应以哪一种说法为准呢？ 这里牵涉到一个英、美两种英语的不同问题。具体到由动词insist, ask, demand, suggest, require, recommend, desire等引导的that从句，在英国英语中，可用should，亦可不用should；但在美国英语中，则一般皆不用should。TOEFL的练习是美国人设计的，故以美国英语为准，不用should。TOEFL还有一些其他标准，不一定为所有的人所接受，但我们只要注意到就可以了。 18 would在此何意？ 有读者问： 有这样一句话： (1)At the house Annie would now be trying to sleep. would何意？ would在此表示推测，相当于汉语的“大概”，所以是一情态动词，不是助动词，再如： (2)It would be about ten when he got home. (3)That would be the book you are looking for. (4)Entered the little lady in her finery... She would not be very old. 顺便提一下，would的现在式will亦可意指“大概”，如： (5)Ask him. He will know. (6)You will remember my brother. (7)This will be the last time that I have dined at this restaurant. 19 关于would like 有读者问： 在初中英语课本中有这样一个句子： (1)What do you think she would like, dear? 这里为何用would? would like是一种常见搭配，亦可看做一种固定说法，其意在此为“想要”，再如： (2)Would you like another cup of coffee? 另外也可意为“愿意”，后常接动词不定式，如： (3)Would you like to come? 20 这里为什么可以用 can? 有读者问：我们的课本上说表“将来的能力”须用 be able, 不可用 can,但我却遇见“Can you ring me up this evening?”请问如何解释？ 应该说，表将来能力(ability)时，一般或通常须用 be able,如： (1)I'll be able to pass my driving test after I've had a few lessons. （亦可用 manage to代替 be able） (2)I'm sure we shall be able to get you a job soon. 但有例外。你所举的一个问句即是一例。我们觉得这种问句中的 can 似乎有 will 的含义，再如： (3)Can you come to the party tomorrow? 另外，在表未来的 if 或 when 从句中亦可用 can，如： (4)If you can pass your driving test at the first attempt, I'll be very surprised. 请再看一种例外情况： (5)The spare parts have arrived. We can repair the car tomorrow.（这里的 can 似乎在表一种由于客观原因而形成的能力） 但请注意下面两句中的 can 则不是表能力，而是表许诺 (permission)： (6)I can see him tomorrow. (7)You can bring the dictionary tomorrow. 21 can不能表未来吗？ 有读者问这样一句话： (1)You can read it next year, maybe. 有人说这里不应用can，而应用will be able to，对吗？ 一般说来，表未来以及过去能做什么，确是应用able，如： (2)We shall be able to finish the work next week. (3)He said they would be able to finish the work the next week. (4)I wasn't able to finish the work in time. (5)I haven't been able to finish the work. 然而，如指很具体而简单的事，can亦可指未来，再如： (6)Can you come to the meeting tomorrow? (7)I can pop in and see you tomorrow. (8)Can 't you find a baby-sitter and come over for dinner? 具体到上述句（1）的确可用will be able to,意为“到了明年你就能读懂这本书了”。如用can，其意则简单地为“你明年可以读此书”。 22 can (could)be 之后不可用 possible 吗？ 有读者问： 有人说 can (could)be 之后不可接 possible, 但我却见过这样的句子： (1)I don't see how that could have been possible. 难道这是一个错句吗？ 这个句子一点也不错。can (could)be 之后完全可接一用作表语的形容词 possible, 再如： (2)How this can be possible is beyond understanding. (3)— Colonel Brandon gave me a living! — Can it be possible? (4)— I stole this. — My dear husband, it can 't be possible!From whom? (5)Could it be possible that they would go back on him now, at the very moment when he was at the threshold of a career? 顺便提及， can (could)还常与副词 possibly 连用， 以加强其语势，如： (6)Mother, I could n't possibly go. Nothing could be worse for me. (7)Can I possibly use your telephone? （possibly 在此表委婉客气） 23 关于cannot have been 有读者问： 我在张汉熙主编的《高级英语》（上册）的第一课中看见这样一个句子： (1)Yet Beethoven cannot have been an easy person to help, for he was quick to show resentment of patronage and social distinction... 请问为什么用现在式cannot而不用过去式could not? 又to help是否用作person的定语？ 表示过去不可能发生的事，可以用“cannot+have+过去分词”，也可以用“could not+have+过去分词”，但could not的语气较cannot为轻。请你千万注意，cannot虽然是现在式，但如后接“have+过去分词”，即表示过去不会发生的事，再如： (2)He can not have missed the way. I explained the route carefully and drew him a map. (3)They can not have been easy to grow. 用“情态动词can+have+过去分词”表过去动作或状态时，除用于否定结构外，亦可用于疑问句 ，如： (4)Can she have done such a thing? (5)Can he have left already? 但要留意，“can+have+过去分词”不可用于肯定结构，例如不可说“He can have gone yesterday.” 但可以说： (6)He could have gone yesterday. 也可以说： (7)He may have gone yesterday. (8)He must have gone yesterday. 24 in order that 之后不可用 can (could)吗？ 有读者问： 有的参考书上说 in order that 之后不可用 can (could), 有的参考书则说可以，孰是孰非，请赐教。 在英国这是一个多年来有争议的问题。早在20世纪20年代，英国有一位大家就说过 in order that 之后用 can (could)与 will (would)无疑是错误的。到了80年代， A.J.汤姆森和 A.V.马蒂内特所著的《牛津实用英语语法》还说 in order that 之后只限于用 may, shall 以及它们的过去式。而英国语法家 L.G.亚力山大所著的《朗文英语语法》则认为 in order that 之后可以用 can (could), 并举例如下： (1)I've arrived early so that/in order that I may/can /will get a good view of the procession. 由此可见，直到如今，在 in order that 之后是否可用 can (could)的问题，在英国仍在争议之中。 在美国的情况如何呢？据近年出版的一本权威著作《韦氏英语惯用法词典》（Webster's Dictionary of English Usage ）说，美国作家和评论家们是不理会 in order that 之后不可用 can （could）这种看法的。 我们认为 in order that 之后可用 can （could)是客观存在。除上述例（1）之外，还有： (2)She has bought the book in order that she can follow the TV lessons. (3)It was as if an immense mass of rocks had been thrown down upon a grassy field; in order that the grass and flowers could bloom again, it was necessary that the pressure should be removed.（作者为一英国文学家） (4)John visited London in order that he could see his MP. （摘自一英国权威语法著作） 最有权威的英人夸克等所著的《英语语法大全》 （A Comprehensive Grammar of the English Language ）一书也认可了 in order that 之后可用 can （could）的现象。 前已提及，美国英语学者一般皆认为 in order that 之后可接 can (could)。这里举一例即可： (5)She turned off the record player in order that her roommate could study. 但有下面几点值得注意： 1. in order that 不及 so that 普通。 2. in order that 是正式英语，较为文气。 3. in order that 较表“目的”的 so that 富有表现力。 4. in order that 常后接 may (might), 有时也后接 should, 而后接 can (could)的情况似乎较少。 5. in order that 后接 can (could)有一种其所表的目的较为明确紧要的含义。 25 can not与cannot之不同 有读者问： can not与cannot有何区别？ 一般说来，二者只是写法不同而已。cannot主要用于英国，can not主要用于美国。也有人认为cannot较为普遍。但强调not时，则常写作can not,如： He can dance, which I can not . 26 这里应选can't be 有读者问这样一道选择题： He knows a lot of things. He_________only five. A. must be B. can't be C. mustn't be D. won't be 为何选B而不选C? must表“推测”时一般只用于肯定结构，否定结构须用cannot，故应选B；must not也有被人用来表“推测”的情况，但不宜为中国学生所模仿。 27 cannot...too...是一固定说法 有读者问： 有一道选择题： (1)If it is the best thing to do, it cannot be done_________soon. A. too B. enough C. much D. ever 答案是A，还是C呢？ cannot...too...是一固定说法，其含意是“怎样……也不为过”。句中it cannot be done too soon的意思即是“它不可能做得快得过头”，其含义是“做此事不论多快也不为过”，也就是说“此事应尽快地做”或“此事做得越快越好”。再如： (2)You cannot be too careful. 你怎样小心也不为过。 (3)You cannot work too hard. 你怎样用功也不为过。 28 could have borrowed与may have borrowed 有读者问如何做这道选择题： — I didn't go to class last night because my car broke down. — You______________mine. I wasn't using it. A. could borrow B. could have borrowed C. may borrow D. may have borrowed 应选B，表示过去可做但未做的事。 29 为什么这里只可用could not have done? 有读者问这样一道选择题： A three-good student_________have done such a thing. A. may not B. might not C. could not D. must not 答案是C，但为什么不可选A，B，D? 应选C。英语中一般不可用may和might的否定完成式。must的否定完成式也可表“可能”，但似乎只可见于美国英语。 30 为什么这里应选用may？ 有读者问如何做这道题： Peter_________come with us tonight, but he isn't very sure yet. A. must B. can C. may D. will 只要明确了所给的四项选择的各自词义即可做出正确的选择。上述四项选择都是情态动词。第一个情态动词是must，它的词义是“必须”或“一定”，选之讲不通。第二个情态动词是can，其词义是理论上“可能”，选之亦讲不通。第三个情态动词是may，它可表具体的“可能”，故正合乎这道题的上下文，因而就可以入选了。那么可不可以选第四个情态动词will呢？ 答案是否定的。其原因是由于它的通常词义是“愿意”，显然不合乎这里的题意。 31 这里不可用 may be 吗？ 有读者问：高中英语第二册有一句： (1)An order has come from Berlin that no language but German may be taught in the schools of Alsace and Lorraine. 有人说 order 后的 that 从句应用虚拟语气，因而 may be 应改为 should be 或 be。对此我有疑问，请释疑。 这个句子乃是摘自著名的故事 The Last Lesson。文字十分规范，不应擅自改动。上述句子一点都不错。这种 that 从句的确常用虚拟语气，而 may be taught 也正是虚拟语气，只不过稍微有点古旧罢了。在这一同位语从句中，事实上不但可用 should be taught 和 be taught, 而且也可以用 may be taught， 甚至还可用 shall be taught。它们都是虚拟语气。试比较下面四种说法： (2)It is my ardent wish that he should come at once. (3)It is my ardent wish that he come at once. (4)It is my ardent wish that he may come at once. (5)It is my ardent wish that he shall come at once. 以上四个句子中的 that 从句（在此用作主语，不用作同位语）用的都是虚拟语气，而这四种虚拟式的意思也都一样。例（2）的 should come 最为普遍，尤其在英国。例（3）的 come 也很常见，尤其在美国。例（4）的 may come 与例（5）的 shall come 则较为古旧，已不多见。但请注意 shall come 的语气要比 may come 强一些。 顺便提及，有时情态动词 must 亦可用于虚拟语气，如： (6)We demand that this burden must be removed. 32 可否用may not have done结构？ 有读者问： 有没有can have done和may not have done等结构？ 可用can have done，但不可用于肯定结构，只用于否定结构和疑问句中，如： (1)He can't have missed the train. (2)Can he have missed the train? 如要说“可能已经……”，应用may have done，如： (3)He may have missed the train. 英语中不可用may not have done结构。如要说“不会误了火车”，应用can的否定完成式，如上述句（1）。 33 must go与must be going 有读者问一道选择题： — It's not very late yet. — I know. But I really must _____ A. be going B. to be going C. have gone D. go 答案是A，为何不选D? must be going有“立即”的含义，must go则没有。 34 这里应选must have been 有读者问这样一道选择题： (1)My pain______________apparent the moment I walked into the room, for the first man I met asked sympathetically, “Are you feeling all right?” A. must be B. had been C. must have been D. had to be 答案是C，我认为A也对，你意如何？ “must have+过去分词”是一完成时态，它可表示的动作或状态必须发生或存在于过去。上述句（1）之所以应选must have been就是这个道理。再如： (2)He must have attended the meeting yesterday. (3)She must have been very young when she got married. must be亦可用以表过去存在的状态，但多用于间接引语中，如： (4)He thought she must be tired. (5)She was sure that he must be Peter. 有时，must be形式上并不用在间接引语中，但实质上（即从上下文看）仍是用在间接引语中，如： (6)There was nobody else in the changing-room. They must all be in the hotel already. 因此，上述句（1）不可选用must be。 35 must have been completed表过去发生的动作 有读者问这样一道选择题： The construction of our library_________by the end of next week. A. must have been completed B. must complete C. must be completed D. must have completed 答案是C，可我觉得A更对，您看呢？ 答案是对的。A不对，因为它只可表推测过去，如把句中的next week改作last week(month，year)，就对了。 36 这里的must也可改为had to 有读者问这样一句话： (1)The people on the train told the boy not to shout, but he insisted that there was danger ahead and that the train must stop at once. 我们认为句中的must应改为had to。不知正确否？ 这个句子中的insisted意谓“坚持说”(declared firmly)，从句that the train must stop at once是它的第二个宾语。这个宾语从句和前一个宾语从句一样，都是间接引语。我们知道，当must意谓“必须”时，在间接引语中它的过去式仍是must，这就是你所问的为什么你所引的句子用must的缘故。这样的must也可改为had to。再如： (2)He said he must go tomorrow. (3)I decided that I must stop smoking. 37 表推测的must不可改作had to 有读者问： (1)I also saw that the camel must be blind in the right eye. 这句话中为什么用must而不用had to? must在此表示“推测”，它和意谓“必须”的must一样，也可用在间接引语中。这里的that从句亦可看做是间接引语。但该句的must又和意谓“必须”的must不一样，它在间接引语中不可改作had to，再如： (2)He thought that I must have lived here for a long time. 表示“推测”的must亦可用在一般的表过去的叙述中，如： (3)He managed to drag himself home where he lay down on the iron cot and remained, panting and gasping. He must have dozed off because he imagined that he was in his hometown. 38 应选 must, be 抑或 can, be？ 有读者问这样一句话： (1)He must be on the playground. 问如何选择填充它的否定句： (2)He_________not_________on the playground. A. must, be B. need, be C.may, be D.can, be 应选A 还是应选 D? 一般说来，如果 must 用以表示推测而意谓“一定”或“准是”的话，那么 must 所在的肯定句变为否定句时，它应变为 can not。问题中肯定句中的 must 显然表示推测，所以否定句应为: (3)He can not be on the playground. （其意是“他不可能在操场上”） 39 must与ought to的区别 有读者问： 汉语中的“这类事情不该做”似乎可以译作： (1)Such things oughtn't to be done. 也可以译作： (2)Such things mustn't be done. 请问二者有何区别？ 这两句话都对。当must意指“义务”时，其义与ought to相似，都可译作“应该”。反之，汉语的“应该”也可译作must或ought to或should。但must的语气最强，它的期望值要大于ought to，而ought to的语气又稍强于should。 40 mustn't, needn't, can't 有读者问： 请解释一下为什么must的否定式有时是mustn't，有时是needn't，有时却是can't? 表“不可”、“不应该”、“不许可”等应用mustn't, 如： (1)You mustn't do that. (2)You mustn't speak like that to your mother. (3)You mustn't cross the border. 表must的反义词应用needn't，如： (4)—Must he come? —No, he needn't . (5)—Must I sign this? —No, you needn't . 表“推测”时，肯定结构用must，否定结构用can't，如： (6)He must have lost his way. （肯定结构） (7)He can't have lost his way. （否定结构） 41 可以说 haven't to 吗？ 有读者问：在Oxford Progressive English Course (Book Two)中有这样一个句子： (1)Her father gave us this house as a wedding present, so we haven't to pay rent. 是否有 haven't to ... 这样的说法？是否应将 haven't to 改作 don't have to? haven't to 并不错，在《牛津现代高级英语学习词典》（Oxford Advanced Learner's Dictionary of Current Engish ）中即有这样的句子： (2)You haven't to go to school today, have you? （也可以说 haven't got to） haven't to 与 don't have to 在意义上没有什么区别，只是前者只用在英国，后者则原只用在美国，但现在亦可用在英国了。英人夸克（R. Quirk)等编著的《英语语法大全》（A Comprehensive Grammar of the English Language ）对下列两个句子进行了比较： (3)Do we have to get up early tomorrow? (4)Have we to get up early tomorrow? 接着他指出句（3）中的“Do we have to...” 在英、美两国皆通用，但句（4）中的“Have we to” 则只用在英国，并说已颇为古旧了。我们认为这样的比较也适用于 haven't to 与 don't have to。 42 have to与will have to稍有不同 有读者问一则改错题： If the volume of British investment is increased, demands on national resources be reduced or . 答案为C错，应改为have to。我认为应改为will have to。请赐教。 have to与will have to都不错，皆可表未来。但have to似乎具有“必然”的含义。 43 关于“it'll have to do” 有读者问： 有这样一个句子： (1)The talk...allowed her to make him a Swiss cheese sandwich and a pot of tea and begin dressing the turkey: salting, peppering, stuffing it with not quite stale enough bread but it'll have to do, ... “it'll have to do”是什么意思？ 为何用将来一般时？ 这是一现成说法，所以上下文虽皆是叙说过去，但仍不改变其时态。它的意思是“就是这样”， 其含意是： 火鸡肉所填塞的面包虽不很新鲜，但这样也就行了。作“行，可以”解的不及物动词do还有如： (2)It will do . (3)That won't do . 44 关于“动词+have to” 有读者问这样一句话： (1)She did not want to have to dodge the caravan continuously. 请解释一下not want to have to，尤其是have to。 这里的have to有点特殊，与其作为情态动词的一般用法（即“情态动词+动词原形”）有所不同。但其本义仍旧是“必须，不得不”。“She did not want to have to dodge...”的意思是： “她不愿意非躲避……不可。”请注意have to不但可用于not want之后，也可用于其他表“不喜欢”等的动词之后，例如： (2)I should not like to have to kill you. (3)I hate to have to get up in the morning. 注意下面一句中的having to代替了to have to: (4)I loathe having to tell you this but... have to还可用于形容词之后，例如： (5)— Did you know my father, Dan Murphy? — He wasn't much, missus, I'm sorry to have to say. have to也常用在be going to之后，但be going to have to则只意味着“将不得不”，例如： (6)I'm going to have to eat something soon. (7)Now you're going to have to hurry, because... (8)This is a revolution! We're going to have to offend somebody. 45 在此had to≠不得不 有读者问这样一道选择题： (1)_____ every day, he had to spend a little time reading books. A. Although busy he was B. Because he was very busy C. However busy he was D. So busy was he 答案是C，但我觉得讲不通，因为had to意为“不得不”。你的看法呢？ had to在此不强调“不得不”，而是意为“需要”（并有“做到了”的含义），再如： (2)Then he had to sit down because he felt dizzy. （had to≠不得不，而是“需要”的意思）。 由此可见，答案C是对的。 46 关于“ought to have+过去分词”的用法 有读者问如何做这道选择题： (1)Tom ought not to_________me your secret, but he meant no harm. A. have told B. tell C. be telling D. having told 这是一道有关情态动词ought to用法的试题。我们知道，ought to之后常接一动词原形，如： (2)We ought to go now. 其否定式是ought not to，如： (3)I ought not to go down town today. “ought to+动词原形”是ought to的一般式。此外，ought to还有完成式和进行式。其完成式是“ought to+have+过去分词”，用以表示过去应完成但却未完成的动作，如： (4)We ought to have done something to help him. （这句话的意思是“我们本该对他有所帮助”，但事实上却未给予帮助） “ought to+have+过去分词”的否定式是“ought not to+have+过去分词”，如： (5)You ought not to have gone to town today. （这句话的意思是“你今天本不该进城”，但事实上你却进城了） 基于上述说明，在试题的4项选择中自应选择A，即have told，其他选择则有的形式不对（如D）；有的形式虽无误，但不符合句意（如B和C）。 47 关于didn't ought to 有读者问： (1)They haven't forgiven me. They think I didn't ought to be lucky like that my first day. 如何解释didn't ought to呢？ 这不是标准英语，有人说是方言。这种说法显然是受了情态动词have to的影响所致，也可与used to类比。didn't ought to在小说中似乎并不罕见，再如： (2)They didn't ought to do that sort of thing. (3)They're best quality, they didn't ought to be so slow catchin'. （they指炉中的煤；catchin'也是非标准英语，即catching） 另外，还有didn't ought to have done的说法，例： (4)You didn't ought to have let that fire out. 48 这里 dare 之后为何没有 to? 有读者问这样一句话： (1)Can you explain why you didn't dare touch the pot, Fred? 这句话中的 dare 是实义动词还是情态动词？如果是实义动词， dare 之后为什么不加 to?如果是情态动词，其前为什么用 didn't? 所问句子中的 dare 仍是情态动词，但如将它看作是情态动词和实义动词的一种混合体，也许更易为人所接受。这种混合体可表示现在时间和过去时间。 表现在时间的混合体有 dare, dares, don't dare, doesn't dare, 现举例如下： (2)Do you dare go? (3)I don't dare go. (4)Who dares go? (5)He dares go. (6)He doesn't dare go. (7)Don't you dare go again! 表过去时间的混合体有 dare, dared, dared not, didn't dare,例如： (8)I dared not go. (9)Dared he go? (10)Did you dare go? (11)I didn't dare go. 所问句子中的 didn't dare touch 即用的是例（11）的 didn't dare go 结构。在当代英语中这种结构在疑问句（如例[10]）和否定句中用得比较普遍。顺便提及，dared not 多用在正式文体中。 49 need 和 dare 何时为情态动词或完全动词？ 有读者问：如何判断 need 和 dare 在句中是完全动词还是情态动词？ 作为情态动词， need 和 dare 的用法与助动词一样，但二者皆无过去式，并多用在否定句与疑问句中，后不可接 to，如： (1)You need not go yet. (2)Need you go yet? (3)You needn't have hurried. (4)I dare not ask him. (5)Dare you ask him?（请注意情态动词 dare 后一般不用完成式） 作为完全动词， need 和 dare 的用法与其他完全动词基本相同。先看 need 的用法： (6)He needs help. （第三人称现在式词尾须加s） (7)Do you need any help?（可与助动词连用） (8)This machine needs to be repaired. （后可接带 to 的不定式） (9)We needed the book very much. （有过去式） (10)This is a book that I have been need ing for a long time.（可用进行时态） 完全动词 dare 的用法也是一样，如： (11)He dares to speak. （to 可不用） (12)Does he dare to speak? （to 可不用） (13)He dared to speak.（to 可不用） 但请注意， dare 没有进行时态。 50 情态动词 need 可用于肯定结构吗？ 有读者问：语法书上说 need 作为情态动词只可用在疑问句和否定句中，不可用在肯定结构中，但我却遇到过这样的句子： (1)All that need be said here may be summed up in a parable or so. need 在此显然用在肯定结构中，不是吗？ 情态动词 need 除多用在疑问句和否定结构中外，有时也可用在肯定结构中，但这种肯定结构一般都有否定的含义。比如例（1）中的 need 即用在肯定结构中，但 all that need be said 却有“除此以外就没有其他需要说的话了”的否定意义。再如： (2)All you need do is get someone to take turns with Pat. (3)All you need do is to take a taxi from the airport. 除可用在上述含有 all 的肯定结构中外，情态动词 need 还可用于含有 only 等词的肯定结构，这种肯定结构亦有“只有这个并无其他”的否定意义，如： (4)He need do it only under these circumstances. (5)Of the other writers, only a few need be dealt with at some length. 下面一句中的 but 亦意谓 only: (6)He need do it but once. 51 “Need we...?”与“Do we need to...?”有区别吗？ 有读者问下面两句话的意思是否一样： (1)Need we come? (2)Do we need to come? 上述两句无甚区别，都可以说，但美国英语多用上述句（2）。 52 这里的 be going to如何解释呢？ 有读者问： (1)What are we going to do? 在这一句中的 are going to 应怎样理解呢？ be going to 有时可用来表示建议或询问对方有什么建议。问句中的 are going to 即有此含义。全句可译为：你看我们该怎么办呢？意即：你有何建议？再如: (2)Let's forget the play. We're going to talk about the future. 我们不去看戏吧，让我们谈谈我们的未来吧。 53 条件句的结果从句不可用be going to吗？ 有一读者问这样一个句子： (1)If you come out for a walk, you are going to feel much better. 据说这句话是错的，句中的are going to应改为will。我不知这种改法是否正确？ 在这个问题上，似乎是有争议的。这句话用will无疑是规范英语，无人会对之提出异议。但如用are going to就会有人反对了，说它是不规范英语。我们的看法是： 在当代英语中，尤其是在美国英语中，“If..., ... be going to...”并不罕见，特别是当be going to表意向的时候，例如： (2)If Tom passes the examination, his father is going to buy him a bicycle. (3)If I have enough money, I'm going to take a trip abroad. 但be going to即使没有意向的含义，结果从句中亦可用be going to，例如： (4)If we don't send him to the hospital quickly, it's going to be too late. (5)What am I going to do if something happens to her? (6)If you invite Jack, there's going to be trouble. 这种用法甚至出之于前美国国务卿基辛格之口： (7)If they harass you after you leave office, I am going to resign as Secretary of State, and I am going to tell the world why! （这是基辛格对即将辞职的尼克松总统讲的话） 54 这里的 was going to 怎么讲？ 有读者问：我们的老师说 was going to 往往指过去未实现的打算或计划，如： (1)I was going to call on you yesterday. 其意是“我本打算昨天去看你的，但却没有去成”。但我却见过这样一句话： (2)I was going to call in the morning. 请问这里的 was going to 该怎样讲呢？ 不错， was going to 的确常可用来表示一种过去未实现的打算或计划，可译作“本打算如何如何”。但它有时并没有“本打算”的含义，恰恰相反，它却可意谓“早已打算或决定如何如何”。你所遇到的“I was going to call in the morning”中的 was going to 即属此义，全句可译为：我早已打算明早打电话的。再如： (3)I was going to stop for a coffee. Would you like to join me? 我早已想停下来喝杯咖啡了，你愿意陪我吗？ 下面一句中的 was going to 与“本打算”就更无关系了： (4)I flunked it; I knew I was going to as soon as I looked at the test problems. 我考砸了，我一看试题就知道要考砸了。 55 这里的 was to 是什么意思？ 有读者问：高中英语第二册第13课 Madame Curie and Radium 中有这样一句话： (1)This something in Madame Curie's own life was to lead science down a new path to a great discovery. 课文注释将 was to 译作“将”，我则认为应将 was to ... 看作是一表语结构，谁对谁错，请赐教。 这里的 was to ... 不是一种表语结构。was to 在此是一种表示“过去的将来”的手段，是 be to 中的一种形式（也有的语法家管它叫做“边际情态动词”）。它在此并不单纯地表示“过去的将来”，而是具有“后来结果”或“注定”的内涵。was to 的这种用法并不罕见，再如： (2)Einstein was still a young man. His discoveries had not yet been published, but they were to change our whole view of the universe. （were to 在此可译作“后来”） (3)While holding Stalingrad the Soviet Army was gathering forces to deal the enemy a blow that was to become the turning point in the war. （这里的 was to become 可译作“后来成为”） (4)The joys of sincere work and worthy aspiration and congenial friendship were to be hers; nothing could rob her of her birthright of fancy or her ideal world of dreams. （were to 可译为“都将为她所有”） 56 there used to be与there was的区别 有读者问下面两个句子的含义有什么不同： (1)There used to be a factory on that corner. (2)There was a factory on that corner. there used to be的含义是“过去曾有，现已不存在了”; there was只意为“过去曾有”，纯指过去，与现在无关。 57 be inclined to可看作情态动词 有读者问这样一句话： I am inclined to think that language has been the most important single factor in the development of man. 怎样分析inclined呢？ 可将be inclined to看作一固定说法。它就像be supposed to, be obliged to, be meant to等一样，也是一种情态动词（有的语法家称之为“半助动词”）。在意义上，be inclined to可以说相当于tend to，都是比较正式的英语。 58 可否用would better？ 有读者问这道选择题： The boy is difficult to deal with. You_________a word with him. A. would better have B. had better have 正确答案是B。是不是没有A这种说法？ 应选B，即had better have。would better（相当于 had better）是美国的非正规的说法，故不可取。would better可能是由于误将缩略式'd better中的'd认为指代would所致。 1 学科网（北京）股份有限公司 $