语态是动词的一种形式，它表示主语和谓语的关系。语态有两种：主动语态和被动语态。如果主语是动作的执行者，或者是说动作是由主语完成的，要用主动语态；如果主语是动作的承受者，或者是说动作不是由主语而是由其他人完成的，则用被动语态。
　　　　英语中的被动语态使用得比汉语要多，要普遍，许多课本乃至实际应用中都常常涉及到这个问题。一般说来，当强调动作承受者，不必说出执行者或含糊不清的执行者时，多用被动式。须注意的是，许多地方与汉语不同。注意那些汉语中没有"被……"的意思，英语却应该用被动态。还要注意，英语的被动态往往由"by"引出，而有用介词"by"的短语往往又不是被动态，而是系表结构。还有些特殊现象，如：known to man(人类......所知)，on foot步行(美国人有时用by foot)，in carraige(乘四轮马车)等等。还有假主动，真被动的十几个常用词的用法，以及so heavy to carry而不用so heavy to be carried 等习惯用法。有关这类情况，做到心中有数对全面掌握被动态，准确无误地解答习题非常关键，被动态必须涉及的是动词的各种时态变化的问题。英语的时态本来很复杂，怎样记住各自的被动形式呢? 首先要明确"将来进行无被动，现在完成进行同"。这两种时态无被动形式。
　　　　另外，不及物动词带有同源宾语的动词，反身代词的动词和系动词都无被动形式。即便如此，还有不定式，动名词，分词，以及它们的复合结构)的被动态，再加上情态动词，助动词以及它们的疑问式和否定式从中掺杂，真是令人头痛，眼花缭乱。下面口诀就以动词do为例，即do did过去式done过去分词，以口诀形式总结各种时态的被动态，一定对你有所启示。
　　　　被动语态（一般现在时）
　　　　主动语态变被动语态时，主动语态句中的宾语变成被动语态句中的主语，主动语态句中的主语成为被动语态句中的动作的发出者。
　　　　被动语态的口诀
　　　　一般现、过用be +过去分词，be有人称、时、数变。
　　　　完成时态have(has) done，被动将been加中间。
　　　　一般将来shall (will) do，被动变do为be done。
　　　　将来进行无被动，shall (will) be doing,
　　　　现在完成进行同，have (has) been doing。
　　　　现、过进行be doing, 被动be加being done。
　　　　情、助、有、是妥安排，一律随新主语变。
　　　　否定助后加not，疑问一助置主前。
　　　　主语恰是疑问词，直陈语序主在前。
　　　　一般情助加be done，双宾多将间宾变。
　　　　复合宾语宾变主，宾补、主补相应变。
　　　　1.一般现在时 is\am\are+P.P(过去分词)
　　　　2.一般过去时 was\were+P.P
　　　　3.一般将来时 will be+P.P
　　　　4.现在进行时 is\am\are+being(固定不变)+P.P
　　　　5.过去进行时 was\were+being(固定不变)+P.P
　　　　6.现在完成时 have\has been+P.P
　　　　7.过去完成时 had been+P.P
　　　　第二句"be有人称、时、数变"即be有人称、时态和单、复数的变化。"情助"是指情态动词和助动词must，may，can，shall，will等一律随新主语(多是主动句中的宾语)来变化。"疑问一助置主前"是说有两个助动词的话，应把主语放在第一助动词之后或把第一助动词置于主语之前。下面详细举例说明之。
　　　　一般现、过用be done, be有人称、时、数变
　　　　例：１、主动：The children gave the foreign guests a warm welcome.
　　　　被动：The foreign guests were given a warm welcome by the children.
　　　　孩子们热烈地欢迎外宾。
　　　　２、主动：People regard him as brilliant.
　　　　被动：He is regarded as brilliant by people.
　　　　人们认为他很有才华。
　　　　以上两例都是一般时态用be done的例子，be有人称、时、数变，第三人称foreign friends是复数，时态一般过去时，所以"be done"就是were given，而People regard him as brilliant一句，被动后的"be done"就变成单数第三人称is regarded的形式了。
　　　　被动：
　　　　This speech was delivered by comrade Wang. (was delivered即一般过去时的被动态)
　　　　这篇讲演是王的发言。
　　　　There was a serious train accident near the border. Two people were killed and twelve were injured.
　　　　边境发生非常严重列车事故，两人死亡，十二人受伤。
　　　　A person who is truly honest is called a straight arrow. 直言不讳的人才是真正诚实的人。
　　　　A note was passed up to the speaker. 有人给讲演者递上来一张纸条。
　　　　John was elected president of the class instead of Harry. 乔治被选为班长而代替了亨利。
　　　　Volcanoes are described as active, dormant or extinct. 火山被描述为活的，沉睡着的，或者死的。
　　　　The soldier was killed, but the train was saved. 这位战士牺牲了，然而列车得救了。
　　　　He was thought to be clever but dishonest. 他被认为很聪明但不诚实。（别人认为他很聪明但不诚实）
　　　　The first zoological garden in the United States was established in 1874. 美国的第一个动物园是1874年建立的。
　　　　Families were often broken up; wives were taken away from their husbands and children from their parents.
　　　　家庭被拆散，妻儿被夺走。
　　　　The information is urgently needed. 急需这个资料。
　　　　Most environmental problems exist because adequate measures for preventing them were not taken in the past. 多数环境污染问题的存在，是因为过去没有采取适当的保护措施。
　　　　完成时态have done，被动将been加中间。
　　　　(过去完成时had done也包括在内)。
　　　　例：１、主动：We have studied English for 3 years off and on at the spare-time school.
　　　　被动：English has been studied for 3 years by us off and on at the spare-time school. (have随新主语变为has)
　　　　我们已经在夜校里断断续续地学了三年英语了。
　　　　２、主动: They had produced 100 tractors by the end of last year.
　　　　被动: 100 tractors had been produced by the end of last year.
　　　　到去年年底我们已生产出一百台拖拉机。
　　　　３、主动：They have set up a power station in their home town.
　　　　被动：A power station has been set up in their home town.
　　　　他们的家乡建立了一座发电站。
　　　　４、主动：They have warned us to be careful of rats.
　　　　被动：We have been warned to be careful of rats.
　　　　他们已提醒我们要注意老鼠。
　　　　５、主动：People have piled plastic bags full of rubbish in streets.
　　　　被动: Plastic bags full of rubbish have been piled in streets.
　　　　人们把装满垃圾的塑料袋子堆放在街上。
　　　　６、主动：We have used nuclear energy to produce electricity.
　　　　被动：Nuclear energy has been used to produce electricity.
　　　　核能已用来发电。
　　　　７、主动：No one has ever beaten him at tennis.
　　　　被动：He has never been beaten at tennis.
　　　　就网球来说还没有人是他的对手。
　　　　(No one涉及到全否定和部分否定问题，见否定一讲)
　　　　The person who owns the gun may try to deny that he has used it. But anyone seeing the smoke knows the gun has just been fired.
　　　　有枪的人会极力否认他开了枪。但是任何看到枪烟(枪冒的烟)的人都会知道刚才开了枪。
　　　　Today is Cilia's wedding day, she has just been married to Bob
　　　　今天是西丽亚的新婚日，她刚刚和鲍勃结婚。
　　　　The subjects of these lectures have been announced by the lecture committee.
　　　　演讲委员会已宣布了这些讲演的题目。
　　　　过去完成时也是一样：
　　　　主动: Somebody had cleaned my shoes.
　　　　被动: My shoes had been cleaned by somebody.
　　　　有人早已把我的鞋子擦了。
　　　　When I returned I found that they had towed (toud) my car away, I asked why they had done this and they told me that id was because I had parked it under a "No Parking Sign".
　　　　被动：my car had been towed away. I asked why this had been done and told that ... it had been parked under a "No Parking Sign".
　　　　当我回来时，发现我的车被弄走了。我问他们为啥这么于。他们告诉我说因为我把车于停在"禁止停车"的禁区。
　　　　主动：They had build three ships by last December.
　　　　被动： By last December three ships had been built by them.
　　　　到去年年底他们已建造了三艘船。
　　　　Research had been centred on the improvement of natural building materials before synthetics were created.
　　　　合成材料造出之前，研究工作集中在改进天然建筑材料上。
　　　　He did not say if all those steel pipes had been examined.
　　　　他并没有说那些钢管都检验过没有。
　　　　After plastic had been created, engineers were given a much wide choice of materials.
　　　　塑料发明之后，工程师们在材料选择上有了更广阔的途径。
　　　　一般将来shall (will) do，被动变do为be done
　　　　即由shall do或will do变为shall done或will be done。
　　　　例：主动: We shall build several big modern power plants in our city next year.
　　　　被动：Several big modern power plants will be built in our city next year.
　　　　过年我市将建立几座大型现代化的发电厂。
　　　　(shall do中的shall要随新主语变为will, do为be done.)
　　　　主动：I shall send my second boy to school next September.
　　　　被动：My second boy will be sent to school next September.
　　　　过年九月我将送我次子去读书。
　　　　主动：In order to fool people cheaps and swindlers will make such bricks out of lead covering the "lead brick" with gold.
　　　　被动：Such bricks will be made out of lead covering the "lead brick" with gold by cheaps and swindlers.
　　　　"铅砖"外面被设法骗钱的商人和骗子们镀上一层金来做这样的"金砖"。
　　　　主动：They will ask you a lot of strange questions.
　　　　被动: You will be asked a lot of strange questions.
　　　　他们将问你许多怪题。
　　　　被动句中的by引出的宾语，一般说来，如果是人称代词你、我、他等，均可省略，someone no one不由by来引出。如果是名词不能省略，但当今英语也都可省略了。
　　　　主动：The Chinese people will make more space explorations in the future.
　　　　被动：More space explorations will be made in the future by the Chinese people.
　　　　中国人民在将来将进行更多的空间探索。
　　　　同样
　　　　After a period of use, the batteries should be changed. 电池使用一段时间后，应该更换。
　　　　Usually, the electricity is on for 24 hours. But tomorrow it will be cut off in the day time. 通常是昼夜供电，明天白天将停电。
　　　　More peaceful uses will be found for nuclear explosives in the future. 在将来会发现更多的和平利用核爆炸的途径。
　　　　More hard work will be needed to make this wonder come true in a short time from now. 从现在起要使这些奇迹在短时间内成为现实还需要做更多的艰苦工作。
　　　　make...come true 使……成为事实; come true做宾补(见感使动词口诀)。
　　　　The machine will not be used again. 这机器不能再用了。
　　　　Will more gas be needed? 需要更多的煤气吗?
　　　　但如果是一般过去将来时如何处理呢？请记下面口诀：
　　　　一般过去将来时，过去某时将发生。
　　　　主动should (would) do，被动be done代原形。
　　　　将来进行无被动，现在完成进行同。
　　　　主动：A few days ago we were still not quite sure whether we should carry out the new plan ahead of time.
　　　　被动：...whether the new plan would be carried out ahead of time.
　　　　几天前，我们还不能肯定能否提前执行新的计划。
　　　　主动：I did not say that we would change the equipment.
　　　　被动：I did not say that the equipment would be changed.
　　　　我并没说过，我们将换掉那台设备。
　　　　主动：My supervisor told me that he would give me a special tutorial a few days ago.
　　　　被动：My supervisor told me that a special tutorial would be given to me a few days ago.
　　　　几天前，我的导师说他将对我进行个别辅导。
　　　　主动: I never thought that be would bring me the information so early.
　　　　被动：I never thought that the information would be brought to me so early.
　　　　我决没想到他那么早就会把资料带给我。
　　　　将来进行无被动，shall (will) be doing,
　　　　现在完成进行同．have (has) been doing,
　　　　即将来进行时表示动作在将来某一时刻或某个阶段正在进行'现在完成进行时表示某-行为发生在过去．延续到现在，可能还要延续下去。两种时态则不用被动语态。
　　　　例；We hope your comany will soon be sending an engineer over to check this equipment. (将来进行时) 我们希望贵公司早些派一名工程师来检查这台设备。
　　　　In a ffew minutes our passenger plane will be flying in the stratosphere. (将来进行时) 几分钟后我们的客机将在同温层中飞行。
　　　　We hope scientists will be tapping new energy sources to meet the need for power. 我们希望科学家们将发掘新的能源来满足能量的需要。(将来进行时)
　　　　What will you be doing this evening? 今晚你将做什么?（将来进行时)
　　　　I have been living in Anshan Since 1980．(现在完成进行时) 1980年以来，我一直住在鞍山。
　　　　How long have you been studying English? 你学英语多久了?(现在完成进行时)
　　　　We have been waiting at the airport for the because of the thick fog. 由于大雾，我们已经在机场等了一整天了。 (现在完成进行时)
　　　　Since then, applied mathematicians have been coping successfully with many problems in astronony. 从那时以来，应用数学家成功地处理了许多天文学上的问题。
　　　　(现在完成进行时)以上均无被动态。
　　　　现、过进行be doing，被动be加being done
　　　　即现在进行时或过去进行时都是be的人称、时和数的形式加doing。而被动态则是be加上being done的形式，being是不变的。现在进行时和过去进行时的被动态是被动态个的重点，容易搞错。例如：
　　　　主动：The workers are repairing the main building of the Northeast Engineering Institute.
　　　　被动：The main building of the Northeast Engineering Institute is being repaired by the workers.
　　　　工人们正在维修东北工学院主楼。
　　　　Two reservoirs are being built at the same time. 两座水库同时建造。
　　　　The nasty question is being considered by the committee members. 委员会的委员们正在考虑那个棘手的问题.
　　　　Equipment and foodstuffs are being flown to the floodstricken areas. 设备和食品正在空运到灾区。
　　　　The buildong of another fly-over is being planned. 他们在计划修建另一座跨线桥。
　　　　We coudld not get through because the February 19th Road was being repaired. 我们过不去，因二.一九路正维修呢。
　　　　情、助、有、是妥安排，一律随新主语变。
　　　　带情态动词和助动词等的被动态如何处理比较复杂。要随新的主语来变化，这些词如can, could；will, would; shall, should; may, might; must; ought to; need需要；have to不得不；be going to; to be to; used to; seem to; happen to等。例如：
　　　　下回书接续！
　　　　接上回书！
　　　　主动: We must keep this in mind.
　　　　被动：This must be kept in mind.
　　　　我们必须把这个记在心里。
　　　　主动：We can put the refrigerator in that place. (refrigerator=freezer.)
　　　　被动：The refrigerator can be put in that place.
　　　　我们可以把电冰箱放在那个地方。
　　　　主动：We shall not use the washing machine again.
　　　　被动：The washing machine will not be used again.
　　　　我们不能再用那台洗衣机了。 原来的谓语shall use被动态中随新主语变为will．
　　　　主动: We shall take more measures to prevent corrosion.
　　　　被动: More measures will be taken to prevent corrosion. (shall变will)
　　　　我们将采取更多的措施来防止腐蚀。
　　　　I ought to be criticized for it. 我应该为此受到批评.
　　　　All this has to be solved with great care. 这一切得认真解决。
　　　　The lobby is going to be rebuilt. 门厅将重建。
　　　　The exhibition is to be opened tomorrow. 展览会将在明日开放。
　　　　再如：
　　　　主动：We shall have to adopt a different attitude.
　　　　被动：A different attitude will have to be adopted.
　　　　我们将不得不采取另一种态度.
　　　　主动：You are to leave the bag here.
　　　　被动: The bag is to be left here. (are to随新主语变为is to)
　　　　你应把包裹放在这儿。
　　　　主动：They used to start these engines by hand.
　　　　被动：These engines used to be started by hand.
　　　　过去他们用手启动马达。
　　　　主动: We are going to paint the wall green.
　　　　被动：The all is going to be painted green.
　　　　我们打算把墙刷成绿色。
　　　　主动：You needn't type this letter.
　　　　被动：This letter need not be typed. (ought to, need是不变助动词)
　　　　你不必把这封信打字。
　　　　主动：John seems to like Mary very much.
　　　　被动：Mary seems to be liked very much by John.
　　　　看来约翰非常喜欢玛丽。
　　　　主动：The boy happened to meet her in the street.
　　　　被动：She happened to be met in the street by the boy.
　　　　这个男孩碰巧在街上遇到了她。
　　　　主动：It must have disappointed him terribly that people told him they didn't want him.
　　　　被动：He must have been terribly disappointed to be told he was't wanted.
　　　　人们告诉他，他们不需要他，这一定已经使得他特别失望.
　　　　主动：You should bear in mind that he wasn't present.
　　　　被动: That he wasn't present should be borne in mind.
　　　　或It should be borne in mind that he wasn't present.
　　　　你应记住他未出席。
　　　　主动：You should have taken those books back to the library.
　　　　被动：Those books should have been taken back to the library.
　　　　你本该把这些书带回图书馆去。
　　　　主动：They may have left it in the sun.
　　　　被动：It may have been left in the sun.
　　　　他们可能已把它放在阳光下了。
　　　　may加不定式的完成体或完成进行体表示"可能"，主要用于肯定句，决不能用在疑问句中。而can与不定式的完成体或完成进行体连用表示"可能"，只用于否定句和疑问句，不用于肯定句。但如果can或may的过去式即could与might与不定式完成体或完成进行体搭配时，可用于各种结构。肯，否，陈，疑均可。
　　　　It can't have been lost in the post, can it?
　　　　它不可能在邮局丢失的吧：(反意疑问句)
　　　　否定助后加not，疑问一助置主前
　　　　在否定句的被动态中，否定副词not-定加在第一助动词之后，不放在别的助动词之后。同样在疑问句的被动态中，第一助动词置于主语之前。
　　　　例：Why has(一助) not anything been(二助) done to end the strike?
　　　　not必须放在第一助动词has之后，第-助动词has必须放在主语anything之前。决不可写成: why has fot been anything done to end the strike?或why has been not anything done to end the strike?
　　　　为什么不采取些措施来结束罢工呢?
　　　　The exercises will not be done in class.
　　　　不可写成：The exercise will be not done in class.
　　　　我们将不在课堂上作练习。
　　　　In what other way could(一助) information about Mars be(二助) abtained?
　　　　用什么别的途径能获得火星的资料呢?
　　　　Why had he been imprisoned?
　　　　他为何入狱的?
　　　　Need she be told about it?
　　　　需要告诉他吗?
　　　　主动：No one has ever equalled your record.
　　　　被动：Your record has never been equalled.
　　　　没人刷新你的记录。
　　　　主语恰是疑问词，直陈语序主在前
　　　　凡主语恰好是一个疑问词或由疑问词来修饰主语时，后面要用陈述语序。
　　　　例: What(主语) could be dropped from a satellite?
　　　　卫星上扔下何物?
　　　　What measures(主语) are being taken to develop this new science? (主语为疑问词what所修饰)
　　　　正在采取什么措施来发展这门新科学?
　　　　What kind of device(主语) is needed to make the control system simple? (主语为疑问词所修饰)
　　　　需要什么装置来使控制系统简化?
　　　　what has been done to improve the techniques?
　　　　采取了什么措施来改进这些技术的? (what恰是句子的主语)
　　　　应指出的是有的学生把We study diligently和She could see herself clearly in the mirror.都硬行变成被动了, 殊不知不及物动词通常是没有被动态的。关于不及物动词．反身代词动词，同源宾语动词．系词．感官使役动词，短语动词的被动态。
　　　　主动句变为被动句所遵循的4个步骤：
　　　　1.把原主动句中的宾语变为被动句的主语
　　　　2.把动词变为被动形式即be +过去分词，并注意其人称和数随主语的变化，而动词的时态则保持不变。
　　　　3.原主动句的主语如需要则放在by后面以它 的宾格形式出现（注代词的宾格），如不需要则可省略。
　　　　4.其它的成分（定语、状语）不变。
　　不用被动语态的情况
　　　　
　　　　1) 不及物动词或动词短语无被动语态（即多数的瞬间动词）：
　　　　appear, die(死亡),disappear（消失）, end (vi. 结束), fail, happen, last, lie, remain, sit, spread, stand
　　　　break out, come true, fall asleep, keep silence, lose heart, take place.
　　　　After the fire, very little remained of my house.
　　　　比较： rise, fall, happen是不及物动词；raise, seat是及物动词。
　　　　(错) The price has been risen.
　　　　(对) The price has risen.
　　　　(错) The accident was happened last week.　
　　　　(对) The accident happened last week.
　　　　(错) The price has raised.　
　　　　(对) The price has been raised.
　　　　(错) Please seat.　
　　　　(对) Please be seated.
　　　　要想正确地使用被动语态，就须注意哪些动词是及物的，哪些是不及物的。特别是一词多义的动词往往有两种用法。解决这一问题唯有在学习过程中多留意积累。
　　　　2) 不能用于被动语态的及物动词或动词短语：
　　　　fit, have, hold, marry, own, wish, cost, notice, watch agree with, arrive at / in, shake hands with, succeed in, suffer from, happen to, take part in, walk into, belong to
　　　　This key just fits the lock.
　　　　Your story agrees with what had already been heard.
　　　　3) 系动词无被动语态：
　　　　appear, be become, fall, feel, get, grow, keep, look, remain, seem, smell, sound, stay, taste, turn
　　　　It sounds good.
　　　　4) 带同源宾语的及物动词，反身代词，相互代词，不能用于被动语态：
　　　　die, death, dream, live, life
　　　　She dreamed a bad dream last night.
　　　　5) 当宾语是不定式时，很少用于被动语态。
　　　　(对) She likes to swim.
　　　　(错) To swim is liked by her.PS:
　　有些动词可以带双宾语
　　　　在用于被动结构时，主动结构中的间接宾语变为主语时，直接宾语仍然保留在谓语后面；直接宾语变为主语时，间接宾语前通常加上介词for/to
　　　　★He was asked a number of questions at the press conference.在记者招待会上人们问了他很多问题
　　　　★They are taught a lot of things in the kindergartens.他们在幼儿园被教给很多东西。
　　　　★A new MP4 was given to him as birthday present/gift.作为生日礼物他收到了一个新MP4。
　　【特别提醒】
　　　　有些动词后跟不带to的不定式作宾语补足语，但改为被动结构后要加上“to”。例如
　　　　We heard him sing in his room just now.
　　　　---He was heard to sing in his room just now.
　　　　刚才听到他在房间中唱歌。
　　　　一、 被动语态的用法：
　　　　1. 一般现在时的被动语态构成：is / am / are + 及物动词的过去分词
　　　　Our classroom is cleaned everyday.
　　　　I am asked to study hard by my mother.
　　　　Knives are used for cutting things.
　　　　2. 一般过去时的被动语态构成：was / were + 及物动词的过去分词
　　　　A new shop was built last year.
　　　　Dinosaur eggs were laid long long ago.
　　　　3. 现在完成时的被动语态构成：has / have + been + 及物动词的过去分词
　　　　This book has been translated into many languages.
　　　　Many man-made satellites have been sent up into space by many countries.
　　　　4. 一般将来时的被动语态构成：will+ be + 及物动词的过去分词
　　　　A new hospital will be built in our city.
　　　　Many more trees will be planted next year.
　　　　5. 含有情态动词的被动语态构成：情态动词+ be + 及物动词的过去分词
　　　　Young trees must be watered often.
　　　　Your mistakes should be corrected right now.
　　　　The door may be locked inside.
　　　　Your homework can be handed in tomorrow.
　　　　6. 现在进行时的被动语态构成：am / is / are + being + 及物动词的过去分词
　　　　Uncle Wang is mending my bike now.→
　　　　My bike is being repaired by Tom now.
　　　　They are planting trees over there. →
　　　　Trees are being planted over there by them.
　　　　7. 不定式的被动语态：to + be + 及物动词的过去分词
　　　　There are two books to be read. →
　　　　There are twenty more trees to be planted.
　　　　二、 怎样把主动语态改成被动语态?
　　　　把主动语态改为被动语态非常简单，可以遵循以下几个步骤：
　　　　1. 先找出谓语动词；
　　　　2. 再找出谓语动词后的宾语；
　　　　3. 把宾语用作被动语态中的主语；
　　　　4. 注意人称、时态和数的变化。
　　　　例：1. Bruce writes a letter every week. →A letter is written by Bruce every week.
　　　　2. Li Lei mended the broken bike this morning.→The broken bike was mended by Li Lei this morning.
　　　　3. He has written two novels so far.→Two novels have been written by him so far.
　　　　4. They will plant ten trees tomorrow.→Ten trees will be planted by them tomorrow.
　　　　5. Lucy is writing a letter now.→A letter is being written by Lucy now.
　　　　6. You must lock the door when you leave.→the door must be locked when you leave.
　　　　三、 使用被动语态应注意的几个问题：
　　　　1. 不及物动词无被动语态。
　　　　What will happen in 100 years.
　　　　The dinosaurs disappeared about 65 million years ago.
　　　　2. 有些动词用主动形式表示被动意义。
　　　　This pen writes well.
　　　　This new book sells well.
　　　　3. 感官动词或使役动词使用省略to的动词不定式，主动语态中不带to ，但变为被动语态时，须加上to 。
　　　　例：make somebody do something→somebody+ be +made to do something
　　　　see somebody do something→somebody +be +seen to do something
　　　　A girl saw my wallet drop when she passed by.→My wallet was seen to drop by a girl when she passed by.
　　　　The boss made the little boy do heavy work.→The little boy was made to do heavy work by the boss.
　　　　4. 如果是接双宾语的动词改为被动语态时，直接宾语(物)作主语，那么动词后要用介词，这个介词是由与其搭配的动词决定。
　　　　He gave me a book.→A book was given to me by him.
　　　　He showed me a ticket.→A ticket was shown to me by him.
　　　　My father bought me a new bike. →A new bike was bought for me by my father.
　　　　5. 一些动词短语用于被动语态时，动词短语应当看作一个整体，而不能丢掉其中的介词或副词。
　　　　We can’t laugh him. →He can’t be laugh by us.
　　　　He listens to the radio every day. →The radio is listened to by him every day.
　　　　The nurse is taking care of the sick man. →The sick man is being taken care of by the nurse.