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1、must用法详解总结 今天给大家带来must用法详解，我们一起来学习吧，下面就和大家分享，来欣赏一下吧。must用法详解1. 表示“必须”、“一定要”(1) 可用于肯定句、否定句或疑问句;用于否定句时，mustnt 的意思是“一定不要”、“不能”，而不是“不必”。如：You must finish it today. 你一定要在今天完成它。You must see the doctor. 你一定要看医生。Must you go so soon? 你一定得这么早就走吗?We mustnt think only of ourselves. 我们可不能只考虑自己。(2) 主要表示现在或将来，但有时(
2、如在间接引语中)也可表过去(=had to)。如：She asked if she must (had to) leave. 她问她是否一定要离开。(3) 对于must 开头一般疑问句，若要作否定回答，可用neednt、dont have to，不用mustnt。如：Must I come over tonight? No, you neednt. “我今晚必须过来吗?”“不必。”(4) 其后可接被动结构或进行形式。如：Something must be done to stop it. 必须采取措施来阻止它。I think I must be going. 我想我得走了。2. 表示推测意为“
3、准是”、“一定是”，注意以下几点。如：(1) 通常只用于肯定句，在否定句或疑问句用 can 代之。如：It must be true. 那一定是真的。比较。如：Can it be true? 那可能是真的吗? / It cant be true. 那不可能是真的。(2) 后接动词原形，表示对现在情况的推测。如：He must be wrong. 他一定错了。The man must have a lot of money. 这个人一定有不少钱。【注】must 表示对现在情况的推测后接动词原形时，该动词通常为状态动词(如 be, have, know 等)，若为动作动词，通常要转换其他说法。如要
4、表示“他一定会赢”，通常不说He must win，可说He is sure to win。(He must win的意思是“他必须要赢”)(3) 其后可接进行式或完成进行式，用以谈论一个正在进行的动作。如：He must be writing a letter to his girl friend. 他一定在给他女朋友写信。Someone must have been smoking here.一定有人一直在这里抽烟。(4) 后接完成式，用来谈论已发生的情况。如：He must have arrived already.他一定已经到了。I didnt hear the phone. I mu
5、st have been asleep. 我没有听到电话铃，我一定是睡着了。3. 表示“应当”相当于should, ought to的意思。如：You must say hello to her.你应当跟她打个招呼。We must go and have a weekend there.我们应当到那里度周末。4. 表示“偏偏”有时表示不巧，有时表示固执，通常都是指令人不快的事。如：Must you make so much noise? 你就非得弄出这么大的声音吗?Why must you always interrupt me? 你为什么硬是老要打断我?We were ready to le
6、ave, but the baby must catch cold. 我们刚准备好要走, 可孩子偏偏得了感冒。Just when I was busy, the neighbor must come and chatter. 正当我忙碌的时候，邻居偏偏过来聊天。什么是情态动词情态动词是一种本身有一定的词义，但要与动词原形及其被动语态一起使用，给谓语动词增添情态色彩，表示说话人对有关行为或事物的态度和看法，认为其可能、应该或必要等。情态动词后面加动词原形。情态动词有四类：只做情态动词：must,can(could),may(might)可做情态动词又可做实义动词：need，will具有情态动词特
7、征：have(had,has) to,used to，ought to情态动词表猜测：一肯一否三不定(must一肯，can not一否，may，might，could，三不定。)注：mustnt代表强烈禁止 must表示主观，have to表示客观。常用的有：can may could must have use .情态动词无人称和数的变化，情态动词后面跟的动词须用原形，否定式构成是在情态动词后面加 “not”。个别情态动词有现在式和过去式两种形式，过去式用来表达更加客气，委婉的语气，时态性不强，可用于过去，现在或将来。情态动词属非及物动词，故没有被动语态。must和have to的用法区别到
8、底在哪里?你“必须”知道 must表示主观上认为有义务或有责任必须做某事，强调说话人的主观看法;have to表示由于客观因素而不得不做某事，强调客观需要。如：Everyone must obey the traffic rules.每个人都必须遵守交通规则。Alices home is very far from her school, so she has to have lunch atschool.爱丽丝的家离学校很远，所以她不得不在学校吃午饭。must没有数和时态的变化，后接动词原形;have to有人称、数和时态的变化，其第三人称单数形式为hasto，其一般过去式为hadto。如：
9、You must say no to smoking and drinking.你必须戒掉烟酒。I shall have to leave London tomorrow.我明天得离开伦敦。在否定句中，mustnt表示“不许，禁止”;dont/doesnt/didnthave to表示“不必，无须”，相当于neednt。如：Look at the sign. You mustnt park here.看那个标志，这里禁止停车。We dont have to/neednt go to school on Sundays.周日我们不必去上学。含有must的一般疑问句，其肯定回答用must，否定回答
10、用neednt或donthave to;回答含有have to的一般疑问句时，要用do的适当形式。如： Must I come back before 9 oclock?我必须在九点以前回来吗? Yes, you must. / No, you dont have to/neednt.是的，你必须。/不，你不必。 Does she have to stay at home on Sunday?她星期天必须呆在家里吗? Yes, she does. / No, she doesnt.是的，她必须(呆在家里)。/不，她不必(呆在家里)。学以致用A. 用must或have to的适当形式填空。1.
11、We wait half an hour for a buslast Sunday.2. This is a public place. You smoke here.3. To catch the first bus, we get up early tomorrow.B. 按要求完成下列各题，每空一词。4. Must I go home at once? (作否定回答) No,you . / No, you .5. David has to stop practising because ofhis illness. (改为一般疑问句，并作肯定回答) David stop practisi
12、ngbecause of his illness? Yes, . Key:1. had to 2. mustnt 3. will have to 4. neednt; dont have to 5. Does; have to; he does英语被动语态不难学，掌握这些就够了!被动语态是动词的一种形式，用以表示主语和谓语之间的关系。当主语是谓语动作的执行者，则为主动语态;当主语是谓语动作的承受者，则为被动语态。例如：They asked the visitors not to touch the exhibits.The visitors were asked not to touch th
13、e exhibits被动语态的构成被动语态由助动词be + 过去分词构成，时态通过be表现出来。如：一般过去时的被动语态：was / were+过去分词。例如:Many trees were planted on the hill yesterday.现在进行时的被动语态：am/is/are+being+过去分词。例如:A new teaching building is being built in our school.注：含情态动词的被动语态：情态动词+be+过去分词。例如：Your homework must be handed in now.使用被动语态时的注意事项1)“get +
14、过去分词”也可以表示被动语态，其中get与be一样起助动词作用。该结构一般用来谈论主语遭受到的变化或不好的事件。例如：Unlike humans, they never get lost and can always find their way back.2)动词带有双宾语的主动结构在变为被动结构时，可以把其中的一个宾语变为主语，另一宾语仍然保留在谓语后面。通常变为主语的是间接宾语。例如：His mother gave him a present for his birthday. He was given a present by his mother for his birthday.(
15、也可改为A present was given to him by his mother for his birthday.)3)当“动词+宾语+宾语补足语”结构变为被动结构时，将宾语变为被动结构中的主语，其余不动。例如：Someone caught the boy smoking a cigarette in the classroom. The boy was caught smoking a cigarette in the classroom.4)在使役动词have, make, let以及感官动词see, watch, notice, hear, feel, observe等后面用不
16、定式作宾语补足语时，在主动结构中不定式to通常省略，但变为被动结构时，要加to。例如：Someone saw a stranger walk into the building. A stranger was seen to walk into the building.5)有些由“动词+介词”、“动词+副词”构成的动词词组，也可以用于被动结构，但要把它们看作一个整体，不能分开，其中的介词或副词也不能省略。例如：Engineers can see how it works and make changes before construction is carried out.6)一些表示“据说
17、”或“相信”的动词如believe, consider, expect, hope, know, report, say, suggest, suppose, think等可以用于句型“It+be动词+过去分词+that从句”或“主语+be动词+过去分词+to do sth.”。例如：Since it is believed that strong smells can affect the senses, volunteers were required not to eat or drink for eight hours before the experiment.Loulan is b
18、elieved to have been gradually covered over by sandstorms from AD 200 to AD 400.谓语动词的主动形式表示被动意义1. 英语中有很多动词如 break, clean, lock, open, sell, read, wash等，当它们用来描述主语(某一事物)的特性时，常用其主动形式表达被动意义，此时主语通常是物。例如：This kind of cloth washes easily. It is popular with young ladies, so it sells well.值得注意的是，主动形式表被动意义强调
19、的是主语的特征，而被动语态则强调外界作用造成的影响。试比较：The door wont lock.(门本身有毛病)The door wont be locked.(不会有人来锁门, 指“门没有锁”是人为原因)2. 连系动词没有被动形式, 但有些表示感受或感官的连系动词(如feel, sound, taste, look, smell等)常以主动形式表示被动意义。例如：I cant see your face, but you sound young. How old are you?3. 动词want，need，require之后的动词和句子的主语是逻辑动宾关系时，常用v-ing的主动形式表被动意义。例如：The table needs repairing. (The table needs to be repaired)must用法详解总结
