12页专四语法总结(编辑修改稿)

12页专四语法总结(编辑修改稿)内容摘要：

(2)下列形容词和分词做表语或补语时， that主语从句中动词用虚拟形式： advisable, desirable, insistent, preferable, urgent, appropriate, pulsory, crucial, essential, imperative, important, necessary, obligatory, possible, probable, proper, vital, advised, arranged, manded, demanded, desired, ordered, proposed, remended, requested, required, suggested。 如 ： The board deem it urgent that these files should be printed right away. It is essential that all these figures be checked twice. (3)下列名词接同位语从句或表语从句时，从句中动词用虚拟形式： insistence, preference, remendation, suggestion, proposal, motion, desire, requirement, request, order, necessity, importance, regulation, rule, resolution, understanding。 如： John Wagner’s most enduring contribution to the study of AfroAmerican poetry is his insistence that it be analyzed in a religious, as well as worldly, frame of reference. They keep telling us it is of utmost importance that our representative be sent to the conference on schedule. 含蓄虚拟语气是指假设条件不通过 if 从句表达，而是暗含在其他结构中。 考生应熟悉： (1)连词 but, but that, or, or else；副词 otherwise, unfortunately等表示转折假设。 如： A safety analysis would have identified the target as a potential danger. Unfortunately, it was never done. Victor obviously doesn’t know what’s happened。 otherwise he wouldn’t have made such a stupid remark. (2)介词短语暗含假设条件，常用的有： without, but for, under more favorable conditions等。 如： But for the English examination I would have gone to the concert last Sunday. (3)intended/meant/hoped/wished/plann或 was/were +不定式完成式或 had intended/meant/planned/hoped/wished +不定式一般式暗示虚拟语气。 如： I intended to have called on you, but I was busy at that time. 6 (4)情态动词完成式暗示虚拟语气。 如： I should have called to make an airline reservation, but I didn’t. (1)从句中动词用过去式 或过去完成式表示虚拟的句型： would rather would as soon as though suppose… had rather would sooner as if supposing… If only… It is (high) time that…(从句中动词只用过去式 ) 如： His wife would rather they didn’t talk about the matter any more. I’d rather you went by train, because I can’t bear the idea of your being in an airplane in such bad weather. If I were in a movie, then it would be about time that I buried my head in my hands for a cry. My father always talks as though he were addressing a public meeting. (2)If it were not for… (与现在事实相反 ) If it had not been for… (与过去事实相反 ) 相当于 but for。 如： If it had not been for his help (= but for his help), we would not have succeeded. (3)If only…谓语动词视情况选用适当的形式。 如： If only the mittee would approve the regulations and put them into effect as soon as possible. (4)lest/for fear that/in case 从句谓语用 (should+)动词原形。 如： The mad man was put in the softpadded cell lest he injure himself. (5)whether… or…有时谓语用 be的原形，引导让步虚拟从句，这种用法经常采用倒装结构。 如： Church as we use the word refers to all religious institutions, be they Christian, Islamic, Buddhist, Jewish, and so on. The business of each day, be it selling goods or shipping them, went quite smoothly. 七、情态动词 注意情态动词完成式的用法有两方面的含义： (1)must have +过去分词，表示对已发生情况的肯定推测，译为“ (昨天 )一定……”。 如： My pain must have been apparent the moment I walked into the room, for the first man I met asked sympathetically: “Are you feeling all right?” (2)can’t/couldn’t have +过去分词，表示对已发生情况的否定推测，译为“ (昨天 )一定没……”。 如： Mary couldn’t have received my letter。 otherwise she would have replied before now. (3)may/might have +过去分词，表示对已发生的事情做不肯定、可能性很小的推测，或事实上根本没发生，译为“也许……”。 如： At Florida Power’s Crystal River plant, a potentially serious leakage of radioactive water may have been unknowingly caused by an electrician. (1)needn’t have+过去分词，表示做了不必做的事，译为“其实没必要……”。 如： As it turned out to be a small house party, we needn’t have dressed up so formally. (2)should /should not have +过去分词，表示应该做某事但实际上未做，或本不应该做但实际上做了 , 译为“本(不 )应该……”。 如： I regret having left the work unfinished。 I should have planned everything ahead carefully. (3)ought to have+过去分词，表示动作按理该发生了，但实际上未发生，译为“该……”，与 should的完成式含义类似。 如： The porter ought to have called the firebrigade as soon as he saw the fire in the stock, which went up in smoke. (4)could have+过去分词，表示过去本来可以做但却未做，译为“完全可以……”。 如： What you said is right, but you could have phrased it more tactfully. (5)may/might have + 过去分词，表示过去可以做但实际未做，译为“ (那样 )也许会……”。 如： It might have been better to include more punchy statistics and photos of equipment in the introduction to further assist firsttime office automation managers. 7 (1)may/might (just) as well“不妨，最好”，与 had better相近。 如： Since the flight was cancelled, you might as well go by train. (2)cannot/can’t…too… “越……越好，怎么也不过分”。 注意这个句型的变体 cannot… over…。 如： You cannot be too careful when you drive a car. The final chapter covers anizational change and development. This subject cannot be overemphasized. (3)usedn’t或 didn’t use to为 used to (do)的否定式。 (4)should 除了“应该”一层意思外，大纲还规定要掌握其“竟然”的意思。 如： I didn’t expect that he should have behaved like that. 八、形容词、副词及其比较级 形容词在句中做定语、表语和主语。 考生应注意： (1)以 “ a” 开头的形容词如 alone, alike, asleep, awake等不能做前置定语，可做表语或后置定语。 (2)某些以副词词缀 “ ly” 结尾的词是形容词，如 friendly, leisurely, lovely等。 (3)下列动词既是实义动词又是系动词，注意用做系动词时，要求形容词做表语： remain, keep, bee, get, grow, go, e, turn, stay, stand, run, prove, seem, appear, look。 ，考生应把握 (1)形容词和副词比较级的形式是否和比较连词对应出现，即是否符合原级比较及比较级的结构。 如： Do you enjoy listening to records? I find records are often as good as, or better than an actual performance. On the whole, ambitious students are more likely to succeed in their studies than are those with little ambition. (2)比较的成分是否属于同类事物或同类概念。 如： The number of registered participants in this year’s marathon was half that of last year’s. Young readers, more often than not, find the novels of Dickens far more exciting than Thackeray’s. (3)比较级的修饰语如 a little, a lot, the, any, even, far, hardly, lots, much, rather，还有表示倍数比较的词等，他们的位置是：修饰语 +as… as… , 或修饰语 +more… than…。 如： Smoking is so harmful to p。