2021考研英语语法动词解析(一)
动词是表示动作或状态的词，根据其意义和作用，动词可分为实义动词、系动词、情态动词和助动词。动词涉及的内容很多，本书仅就研究生考试中常涉及的动词时态、时态一致以及部分情态动词作深入讲解。
一、时态(Tense)
时态是表示动作发生的时间和表现方式的一种动词形式，英语动词的时态有16种，但在研究生考试以及其他考试中常考的时态只有几种。不管何种时态，所包含的主要内容都是相同的，即时态的构成以及用法。本书着重讲解重要时态的用法。
(一)一般现在时(Simple Present Tense)
1. 表示客观真理或科学事实。
例句： The moon has a mass that is nearly one hundred times less than that of the earth;in consequence, the force of gravity at the moon’s surface is only one-sixth of that at the earth’s surface.
分析： 该句是复合句，定语从句that is nearly...less than that of the earth修饰a mass;in consequence后是另一个并列句。
译文： 月球的质量差不多是地球质量的1/100，因此月球表面的引力只有地球表面引力的1/6。
例句： One difficulty in translation lies in obtaining a concept match. By this is meant that a concept in one language is lost or changed in meaning in translation. (2001年第8题)
分析： 该句由两个句子构成，前一个是简单句，后一个句子是复合句;that后是一宾语从句。
译文： 翻译中的一个难点在于找到一个相对应的概念。这就是说，在翻译过程中一种语言的概念会丢失或发生意义上的改变。
2. 表示现在反复发生或习惯性的动作以及存在的状态，常与always，often，usually， sometimes， once a week，seldom，never等时间状语连用。
例句： It’s usually the case that people seldom behave in a rational way when in a furious state.
分析： 该句是复合句，从句that people seldom behave in a rational way是the case的同位语;when后省略了people are。
译文： 人们在暴怒时通常会丧失理智。
例句： Physicians frustrated by their inability to cure the disease and fearing loss of hope in the patient too often offer aggressive treatment far beyond what is scientifically justified. (选自2003年Text 4)
分析： 该句是复合句，其中主干部分为physicians too often offer aggressive treatment...。分词短语frustrated by their inability to cure the disease and fearing loss of hope in the patient作physicians的后置定语;从句what is scientifically justified作介词beyond 的宾语。
译文： 医生由于不能够治愈疾病，同时又担心病人失去希望，因而常常采用极端大胆的治疗方法，这些方法远远超过了科学所能认同的界限。
3. 表示按计划进行的将来动作，常用come，arrive，catch，fly，leave，go，start等词。
例句： When he comes, please inform him of all that I have just told you.
分析： 该句是复合句。该复合句中包含when引导的时间状语从句和that引导的定语从句。
译文： 他来时，请转告他我告诉你的一切。
4. 用在时间或条件状语从句中表示将来的动作。
例句： He will come the moment he finishes his work.
分析： 该句中的the moment为连词，意为“一……就”，相当于as soon as。
译文：他一结束工作就会来。
例句： If it is fine tomorrow, we’ll go shopping.
译文： 如果明天天气好的话，我们将去逛商场。
5. 表示主语的能力、性格、个性等。
例句： As an industry, biotechnology stands to rival electronics in dollar volume and perhaps surpass it in social impact by 2020. (2001年第25题)
分析： 该句是简单句，surpass前省略了不定式to。
译文： 作为一门产业，生物技术在营业额上可以与电子业相媲美，并且到了2020年还有可能在社会影响上超过它。
例句： The director treats his staff as equals.
译文： 主任对其下属一视同仁。
6. 表示格言或警句。
例句： A fence needs the support of three stakes; an able fellow needs the help of three other people.
译文： 一个篱笆三个桩，一个好汉三个帮。
例句： Histories make men wise; poets witty; the mathematics subtle; natural philosophy deep; moral grave;logic and rhetoric able to contend.
译文： 读史使人明智，读诗使人灵秀，数学使人周密，科学使人深刻，伦理使人庄重，逻辑修辞之学使人善辩。
(二)现在完成时(Present Perfect Tense)
1. 已完成用法： 表示动作在过去某一不明确的时间已完成，强调对现在的影响，这一用法常不带时间状语或可与不明确的时间状语连用，如： already，yet，ever，just，never。
例句： I have excluded him because, while his accomplishments may contribute to the solution of moral problems, he has not been charged with the task of approaching any but the factual aspects of those problems. (2006年第48题)
分析： 该句是复合句。在because引导的原因状语从句中又加入了由while引导的让步状语从句。
译文： 我之所以将他(普通科学家)排除在外，是因为尽管他的成果可能有助于解决道德问题，但他承担的任务只不过是研究这些问题的事实方面。
例句：The same dramatic technological changes that have provided marketers with more (and more diverse) communications choices have also increased the risk that passionate consumers will voice their opinions in quicker, more visible, and much more damaging ways. (选自2011年Text 3)
分析：该句是复合句。主句的主干部分是The same dramatic technological changes have also increased the risk。that have provided marketers with more (and more diverse) communications choices是一个定语从句，修饰changes;that passionate consumers will voice their opinions in quicker,more visible, and much more damaging ways是risk的同位语从句，介词短语in quicker, more visible, and much more damaging ways在该同位语从句中作状语，表示方式，修饰谓语动词voice。
译文：同样是这些重大的技术变革，在给营销商带来更多的(以及更多样化的)传播渠道选择的同时，也增加了风险，那就是热情洋溢的消费者将会以更快、更明显和更具破坏性的方式表达他们的观点。
2. 未完成用法： 表示动作从过去某时开始持续到现在，还有可能持续下去，强调持续性，这一用法要带表示一段时间的状语，如： recently, these days, for 3 years, since 2000, over the past等。
例句： For example, it has long been known that total sleep deprivation is 100 percent fatal to rats, yet, upon examination of the dead bodies, the animals look completely normal.
分析： 该句是复合句。
译文： 比如，人们早已知道，完全剥夺其睡眠对老鼠而言绝对是致命的。然而，在检验动物尸体时，那些动物看起来是完全正常的。
例句： Since the dawn of human ingenuity, people have devised ever more cunning tools to cope with work that is dangerous, boring, burdensome, or just plain nasty. (选自2002年Text 2)
分析： 该句是复合句。句中定语从句that is dangerous，boring，burdensome...修饰work， since...在句中作状语。
译文： 自从人类具有了独创性以来，人们就发明了愈加精巧的工具来处理那些危险、无聊、麻烦或者仅仅是令人讨厌的工作。
3. 现在完成时用于时间或条件状语从句中表示将来完成的动作。
例句： I’ll help you when I have finished my work. I will return the book if I have finished it.
4. 下列表达方式后要用现在完成时。
This (That/It) is the first (second...)...
This (That/It) is the best (finest/worst/most interesting...)...
例句： This is the first time that China has had such negotiations with a G-7 member, the official said.
译文： 该官员说，这是中国与七国集团成员首次进行这样的谈判。
例句： This is the first time that he has felt really relaxed for months.
译文： 几个月来他第一次真正感到放松。
注意： 如果主句动词表示过去时间，从句常用过去完成时;如果主句动词表示将来时间，从句仍使用现在完成时。
例句： It was the best picture that she had seen.
It will be the best picture that she has seen.
5. 有些时间状语常用于现在完成时态。
如：
up till nowso farat (for) the past (last) years
in recent yearsup to present
例句： For the past several years, the Sunday Newspaper supplement Parade has featured a column called“Ask Marilyn”. (选自2007年Text 2)
分析： 该句是简单句，其中called“Ask Marilyn”作后置定语，修饰a column。
译文： 在过去的几年里，《展示杂志》周日增刊上出现了一个叫做“向玛瑞林提问”的特色专栏。
(三)过去完成时(Past Perfect Tense)
1. 表示过去某时刻以前发生和完成的动作，即过去的过去，常用于主从复合句中。
例句： She felt suitably humble just as she had when he had first taken a good look at her city self，hair waved and golden，nails red and pointed. (2001年第4题)
分析： 该句是复合句。when引导的时间状语从句用的是过去完成时，所以主句只能用过去的时态;由于主句用的是一般过去时felt，那么其时间状语应用过去完成时，即 as后的完整形式应是as she had felt。
译文： 她举止谦逊、得体，就像他当初见到她时她所表现的那样： 金黄色的卷发，尖尖的红指甲。
例句： Bolivar had received aid from Haiti and had promised in return to abolish slavery in the areas he liberated. (选自2007年Use of English)
分析： 该句是复合句。he liberated是修饰the areas的定语，在从句前省略了作宾语的关系 代词which或that。
译文： 玻利瓦尔接受过海地的援助，作为同报，他承诺在解放的地区废除奴隶制。
2. 用于hardly...when， scarcely...when(before)， no sooner...than(刚一……就)句型中。当hardly，scarcely，no sooner置于句首时，句子结构要倒装。
例句： No sooner had we reached the top of the hill than we all sat down to rest.
Hardly had the teacher entered the classroom when the pupils were in absolute silence. (be in absolute silence可译为“鸦雀无声”)
3. 用于虚拟语气条件句中，表示与过去事实相反的假设。
例句： I would have gone to visit him in the hospital had it been at all possible, but I was fully occupied the whole of last week. (1997年第4题)
分析： 该句是并列复合句。had it been at all possible是省略了if的倒装句，完整形式应为 if it had been...;本句but前是一个非真实条件句，表示与过去事实相反的假设。
译文： 如果有一点可能的话，我都会到医院去看望他，但我上个礼拜整个一周都没有空。
4.动词hope，expect，think，intend，want，mean，suppose，plan，believe等用于过去完成 时，表示未实现的希望、意图、计划等。
例句： Mr. Pelkmans is not among those who had believed that the EC’s single market is threatened by the doubt building over Europe’s continued integration.
分析： 该句是复合句。定语从句who had believed...修饰those;that the EC’s single market is threatened...作believed的宾语;分词短语building over...作定语修饰the doubt。
译文： 有些人原以为对促进欧洲持续整合怀有的疑虑会威胁到欧共体的统一市场，佩尔克斯曼先生并不这么认为。
注意： 当连词after指明两个过去动作的时间先后顺序时，after从句中可用过去完成时，也可用一般过去时;在连词when引导的从句中，有时过去完成时与一般过去时可以互换使用;当before用作连词引导从句时，主句中过去完成时与一般过去时也可互换使用。
例句: Julia left the room after she had turned off (turned off) the light.
When the teacher had left (left) the room, the pupils started talking.
Before he entered college, he had served (served) in the army.