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【摘要】: 科技人员在用英语说明情况或讨论问题时, 习惯于多用能够体现客观性的无人称被动句。因此在科技文献中频繁出现被动语态。本文先用将被动语态与主动语态进行对比的方法介绍有关被动语态的基础知识。然后参考和引用一些论述科技问题的例句来具体说明被动语态在科技英语中的应用情况。 Abstract: Scientists prefer to use impersonal passive sentences when they talk or write about their work. After a brief introduction of the fundamentals of passive voice, its application in scientific English will be discussed in this thesis. 在科技文章中, 多数句子是无人称被动句,因为科技著作者想要客观地对待事物, 而不强调行为的主体, 所以通常不用“I”、“you” 或“the operator”等作为句子开头。[1](P64) 一、被动语态语态表示句中主语和谓语动词之间的关系。若主语是动作的执行者, 动词用主动语态, 当主语是动作的承受者, 动词要用被动语态。只有及物动词才有被动语态。[2](P178)例如: His father planted this tree.( 主动语态) This tree was planted by his father.( 被动语态) A pump supplies compressed air. ( 主动语态) Compressed air is supplied by a pump. (被动语态) 被动语态由动词be 和及物动词的过去分词构成。被动语态与主动语态的对应关系、被动语态一般时、进行时和完成时的常用句型, 可用以下各组例句概略说明: They will find it out. It will be found out. We keep the butter here.[3](P263) The butter is kept here. Did she open that letter? Was that letter opened by her? A mechanic is repairing your car. Your can is being repaired by a mechanic. They were painting that house. That house was being painted by them. They have already found him. He has already been found. They had opened this road to traffic. This road had been opened to traffic. 构成被动语态的动词be, 在口语中有时可用get代替, 例如: You' ll get sacked if you often leave early. Look out, you may get hurt. The eggs got broken when I slipped. Mr. Li got married last week. 二、使用被动语态的主要场合[3](P266) (1) 表述人认为不必提及动作的执行者, 例如: Your leg will be X- rayed. Are the streets swept everyday? Considerable progress has already been made. ( 2) 表述人不知道或不能肯定动作的执行者, 例如: Is your bike stolen? You will be met at the airport. They' ve been told that he is no longer here. He is supposed to be living in Shanghai. This sort of ad is seen everywhere. ( 3) 为了缓和语气, 回避责任, 故意不说明动作的执行者, 例如: Someone has opened this letter. We are going to reduce overtime rates. 可以修改成为: This letter has been opened. Overtime rates will be reduced. 显然, 与前两句相比, 后两句的语气比较缓和。 ( 4) 表述人对事件本身比对事件的动因更为重视, 例如: Three men were killed in the accident. A modern hospital is being built near here. The spy has already been caught. ( 5) 为了使表述更为通顺流畅试比较下面的两个句子: When he arrived home a policeman arrested him. When he arrived home he was arrested by a policeman. 前一句中间变换了主语, 后一句则无此缺点。又如: When she was ill neighbors looked after her child. When she was ill her child was looked after by neighbors.[3](P266) 在这里, 由于类似原因, 也是后一句更为通顺。三、科技英语中的被动语态下面给出的是关于造船技术、核反应堆、桥梁工程和石油化工的四组无人称被动句。句子的参考译文附在每组例句的后面。由这些例句不难看出无人称被动句在科技英语中的应用情况, 了解专业人员用英语论述科技问题时的言谈方式和行文特点,以及被动语态在科技英语中出现的频繁程度。 Computers can also be used to automate shipbuilding. That has already been done in many ways.[4](P83) Not long ago steel plates were still marked out by hand. This method was replaced by optical following. Therefore steel plates are cut automatically by gas burners. Nowadays the cutting machine is controlled by information stored on computer tape. This is called numerical control. 计算机还可用于使造船业实现自动化。这在许多方面已经实现了。不久前钢板还要用手工画出大样。后来光学跟踪代替了这一方法。因而钢板能用气割枪自动切割出来。现在则是用计算机磁带中储存的信息控制切割机。这就叫作数字控制方法。 The chain reaction must be carefully controlled.[4](P49) This is done by absorbing excess neutrons in boron control rods. The heat is transferred by circulating carbon dioxide gas. The hot gas is used to produce steam. The whole assembly is called a nuclear reactor. 对链式反应必须谨慎控制。这要用硼控制棒吸收多余的中子来完成。热量由循环流动的二氧化碳气传送。高温气体则用于产生水蒸气。整个组合体称为核反应堆。 Su