這段文字是畢業(yè)論文里的,怎么翻譯成英文,最好是被動語態(tài)

【專家解說】：被動語態(tài)中主語是動作的承受者而不是發(fā)出者 結(jié)構(gòu)為主語+be的過去式+動詞過去分詞（不是過去式） 有時在句末+by sth/sb(動作的發(fā)出者) Do the students water the flowers every day? Do the flowers were watered by the students every day? tom gave mike a pen yesterday Mike was gaven A pen by mike yesterday they will sing an english song at the party An english song would be singd by they at the party. 或者 an english song at the party would be singd by they 英語中的被動語態(tài)使用得比漢語要多，要普遍，許多課本乃至實際應(yīng)用中都常常涉及到這個問題。一般說來，當強調(diào)動作承受者，不必說出執(zhí)行者或含糊不清的執(zhí)行者時，多用被動式。須注意的是，許多地方與漢語不同。注意那些漢語中沒有"被……"的意思，英語卻用被動態(tài)。還要注意，英語的被動態(tài)往往由"by"引出，而有用介詞"by"的短語往往又不是被動態(tài)，而是系表結(jié)構(gòu)。還有些待殊現(xiàn)象，如…knownto man(人類......所知)，on foot步行(美國人有時用by foot)，in carraige(乘四輪馬車)等等。還有假主動，真被動的十幾個常用詞的用法，以及so heavy to carry而不用so heavy to be carried等習慣用法。有關(guān)這類情況，做到心中有數(shù)對全面掌握被動態(tài)，準確無誤地解答習題非常關(guān)鍵，被動態(tài)必須涉及的是動詞的各種時態(tài)變化的問題。英語的時態(tài)本來很復(fù)雜，怎樣記住各自的被動形式呢? 首先要明確"將來進行無被動，現(xiàn)在完成進行 同"。這兩種時態(tài)無被動形式。 另外，不及物動詞帶有同源賓語的動詞，反身代詞的動詞和系動詞都無被動形式。即便如此，還有不定式，動名詞，分詞，以及它們的復(fù)合結(jié)構(gòu))的被動態(tài)，再加上情態(tài)動詞，助動詞以及它們的疑問式和否定式從中摻雜，真是令人頭痛，眼花繚亂。下面口訣就以動詞do為例，即do did過去式done過去分詞，以口訣形式總結(jié)各種時態(tài)的被動態(tài)，一定對你有所啟示。 被動語態(tài)的口訣 一般現(xiàn)、過用be done，be有人稱、時、數(shù)變。 完成時態(tài)have done，被動將been加中間。 一般將來shall (will) do，被動變do為be done。 將來進行無被動，shall (will) be doing, 現(xiàn)在完成進行同，have (has) been doing。 現(xiàn)、過進行be doing, 被動be加being done。 情、助、有、是妥安排，一律隨新主語變。 否定助后加not，疑問一助置主前。 主語恰是疑問詞，直陳語序主在前。 一般情助加be done，雙賓多將間賓變。 復(fù)合賓語賓變主，賓補、主補相應(yīng)變。 第二句"be有人稱、時、數(shù)變"即be有人稱、時態(tài)和單、復(fù)數(shù)的變化。"情助"是指情態(tài)動詞和助動詞must，may，can，shall，will等一律隨新主語(多是主動句中的賓語)來變化。"疑問一助置主前"是說有兩個助動詞的話，應(yīng)把主語放在第一助動詞之后或把第一助動詞置于主語之前。下面詳細舉例說明之。 一般現(xiàn)、過用be done, be有人稱、時、數(shù)變 例：1、主動：The children gave the foreign guests a warm welcome. 被動：The foreign guests were given a warm welcome by the children. 孩子們熱烈地歡迎外賓。 2、主動：People regard him as brilliant. 被動：He is regarded as brilliant by people. 人們認為他很有才華。 以上兩例都是一般時態(tài)用be done的例子，be有人稱、時、數(shù)變，第三人稱foreign friends是復(fù)數(shù)，時態(tài)一般過去時，所以"be done"就是were given，而People regard him as brilliant一句，被動后的"be done"就變成單數(shù)第三人稱is regarded的形式了。 被動： This speech was delivered by comrade Wang. (was delivered即一般過去時的被動態(tài)) 這篇講演是王的發(fā)言。 There was a serious train accident near the border. Two people were killed and twelve were injured. 邊境發(fā)生嚴重列車事故，二人死亡，十二人受傷。 A person who is truly honest is called a straight arrow. 直言不諱的人才是真正誠實的人。 A note was passed up to the speaker. 有人給講演者遞上來一張紙條。 John was elected president of the class instead of Harry. 喬治被選為班長而代替了亨利。 Volcanoes are described as active, dormant or extinct. 火山被描述為活的，沉睡著的，或者死的。 The soldier was killed, but the train was saved. 這位戰(zhàn)士犧牲了，然而列車得救了。 He was thought to be clever but dishonest. 他被認為很聰明但不誠實。 The first zoological garden in the United States was established in 1874. 美國的第一個動物園是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，妻兒被奪走。 The information is urgently needed. 急需這個資料。 Most environmental problems exist because adequate measures for preventing them were not taken in the past. 多數(shù)環(huán)境污染問題的存在，是因為過去沒有采取適當?shù)谋Ｗo措施。 完成時態(tài)have done，被動將been加中間。 (過去完成時had done也包括在內(nèi))。 例：1、主動：We have studied English for 3 years off and on at the spare-time school. 被動：English has been studied for 3 years off and on at the spare-time school. (have隨新主語變?yōu)閔as) 我們已經(jīng)在夜校里斷斷續(xù)續(xù)地學了三年英語了。 2、主動: They had produced 100 tractors by the end of last year. 被動: 100 tractors had been produced by the end of last year. 到去年年底我們已生產(chǎn)出一百臺拖拉機。 3、主動：They have set up a power station in their home town. 被動：A power station has been set up in their home town. 他們的家鄉(xiāng)建立了一座發(fā)電站。 4、主動：They have warned us to be careful of rats. 被動：We have been warned to be careful of rats. 他們已提醒我們要注意老鼠。 5、主動：People have piled plastic bags full of rubbish in streets. 被動: Plastic bags full of rubbish have been piled in streets. 人們把裝滿垃圾的塑料袋子堆放在街上。 6、主動：We have used nuclear energy to produce electricity. 被動：Nuclear energy has been used to produce electricity. 核能已用來發(fā)電。 7、主動：No one has ever beaten him at tennis. 被動：He has never been beaten at tennis. 就網(wǎng)球來說還沒有人是他的對手。 (No one涉及到全否定和部分否定問題，見否定一講) 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. 有槍的人會極力否認他開了槍。但是任何看到槍煙(槍冒的煙)的人都會知道剛才開了槍。 Today is Cilia's wedding [font id=Mark style="COLOR: blue; BACKGROUND-COLOR: #ccffff"]day[/font], she has just been married to Danel. 今天是西麗亞的新婚日，她剛剛和丹尼爾結(jié)婚。 The subjects of these lectures have been announced by the lecture committee. 演講委員會已宣布了這些講演的題目。 過去完成時也是一樣： 主動: Somebody had cleaned my shoes. 被動: 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". 被動：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". 當我回來時，發(fā)現(xiàn)我的車被弄走了。我問他們?yōu)樯哆@么于。他們告訴我說因為我把車于停在"禁止停車"的禁區(qū)。 主動：They had build three ships by last December. 被動： By last December three ships had been built by them. 到去年年底他們已建造了三艘船。 Research had been centred on the improvement of natural building materials before synthetics were created. 合成材料造出之前，研究工作集中在改進天然建筑材料上。 He did not say if all those steel pipes had been examined. 他并沒有說那些鋼管都檢驗過沒有。 After plastic had been created, engineers were given a much wide choice of materials. 塑料發(fā)明之后，工程師們在材料選擇上有了更廣闊的途徑。