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2008-08-10 22:04:36
5、谓语的“能愿语态”(即传统语法所说的“情态”)
当表达“能够….、愿意…..、可能…….，或许……，必须….”等意思时，句子的谓语也要“变脸”，由于这种变脸是因为“能力”和“心愿”而产生的，我们把这种情况下的谓语变脸叫做“能愿语态”
“能愿语态”的变脸的方法一般是：
将来、能愿助动词 + v(动词原形)
它的谓语公式具体细分为“一般能愿语态”和“过去能愿语态”，“一般能愿语态”用在一般现在时间里，“过去能愿语态”的使用时间比较模糊，既能使用在一般过去时间里，也能使用在一般现在时间里，它常用来表达委婉客气的要求。
注意：能愿语态的谓语公式和将来时态的谓语公式十分相近。
He can speak English.
You must do it.
I have to stay here.
He must be an actor.
We should be there now.
It should be repaired soon.
特别提示：
在语法大表2第9、10两组谓语公式的后面有一个向上的箭头线“猜测”，这条线表示：当过去将来、能愿助动词动词后面加上完全助动词have时，并继续接have后面完成时态的部分时，表达对过去已经发生完毕的事件的猜测。如：
They might have done this.
They should have finished their work.
This work might have been finished by them.
He did best in the test，he must have worked hard.
I might have come to the wrong conclusion.
需要注意的是，有些将来、能愿助动词与将来助动词是一样的词，比如will、shall、would、should等，而且它们都安放在动词原形的前面，这两种助动词可根据句子的含义来区别：当句子的含义侧重于表达“将来”时，这个助动词就是将来助动词，当句子的含义侧重于表达“能愿”时，这个助动词就是将来、能愿助动词。
6、谓语的“强调语态”
当表达“确实….、的确…..、真的…..、绝对….、”等意思时，句子的谓语也要“变脸”，由于这种变脸是因为“强调”而产生的，我们把这种情况下的谓语变脸叫做“强调语态”。就是用助动词do (did，does) 强调谓语。强调语态仅用在三种谓语公式里，即1-1，1-7，2-1公式。
I do speak English.
He did come here yesterday.
He does have a happy family.
7、谓语的“虚拟语态”(假设句的时间与推断句的时间前后相连)
1)、概念
虚拟语态用来表示说话人的主观愿望或假想，所说的是一个条件，不一定是事实，或与事实相反(事情不可能发生) (比如说“如果恐龙还活着的话…..”)，句子的谓语也要“变脸”，由于这种变脸是因为“假设”而产生的，我们把这种情况下的谓语变脸叫做“虚拟语态”。
因此虚拟的句子有两处谓语要变脸，一处是“虚拟假设”中的谓语，一处是“虚拟推断”句中的谓语，他们联合起来变脸。
2)、在条件句中的应用
条件句可分为两类，一类为真实条件句，一类为非真实条件句。非真实条件句表示的是假设的或实际可能性不大的情况，故采用虚拟语态。
(1)、真实条件句
真实条件句用于陈述语态，假设的情况可能发生，其中 if 是”如果”的意思。
时态关系
句型： 条件从句 主句
一般现在时 shall/will + 动词原形
If he comes, he will bring his violin.
The volleyball match will be put off if it rains.
分析：真实条件句主句为将来时，从句用一般现在时。
注意：
A、在真实条件句中，主句不能用be going to表示将来，该用shall, will.
(错) If you leave now, you are never going to regret it.
(对) If you leave now, you will never regret it.
B、表示真理时，主句谓语动词便不用shall (will) +动词原形，而直接用一般现在时的动词形式。
(2)、非真实条件句
①、概念
虚拟语态常用在“如果……，那么…..”的说话句型中，前为一个虚拟的假设，他假设一个不可能发生的条件，后者是一个虚拟的推断，它同样推断一个不可能发生的结果。
②、虚拟语态的变脸方法
即：“提前一个时态”，具体的提前一个时态的操做方法如下：
|
|
if条件句的谓语 |
主句的谓语 |
|
与现在事实相反 |
Were |
would (could/should/might) + do |
|
did | ||
|
与过去事实相反 |
had done |
would (could/should/might) + have done |
|
与将来事实相反 |
did/were |
would (could/should/might) + do |
|
should do | ||
|
were to do |
③、虚拟语态具体用法
A、当假设的情况是当前或将来不可能发生的事情时，假设句和推断句均提前一个时态：
“假设句”中的谓语用“一般过去时态”或“过去将来时态”并且系动词均用were，而不用was（见2-2红字）。
“推断句”中的谓语用“过去将来时态”(见2-6红字)。
If I were you，I would refuse the work.(2-2,6-1公式)
If I had enough money，I would buy a computer. (2-1,6-1公式)
If I had time，I should go with you. (2-1,6-1公式)
If it would snow tomorrow，I would not go out. (6-1,6-1公式)
If they were here, they would help you.
If I were to do the work, I should do it in a different way.
要是我做这项工作，我就会以不同的方式去做。(其假设成份很大，实现的可能性很小)
If the headmaster were to come, what would we say to him?
假如校长来了，我们对他说什么呢？
If you succeeded, everything would be all right.
If you should succeed, everything would be all right.
If you were to succeed, everything would be all right.
比较：If I do和If I did两种结构都可以表示现在或将来。If I do表示可能性较大，而If I did表示可能性较小，或完全没有可能。
If I win the race...如果我跑了第一名……(运动员这样说)
If I won first prize...如果我中了一等奖……(买彩票的人这样说)
If I become president, I'll...如果我当总统，我就……(竞选总统的候选人这样说)
If I became president, I'd...如果我当总统，我就……(一个小学生这样说)
B、当假设的情况是过去不可能发生的事情时，假设句和推断句均提前一个时态：
“假设句”中的谓语用“过去完成时态”（见2-4红字）。
“推断句”中的谓语用“过去将来完成时态”(见2-8红字)
If I had come yesterday,I would have finished this work. (4-1,8-1公式)
If I had left soon yesterday,I would have caught the bus. (4-1,8-1公式)
If I had taken you advice, I should have passed the exam. (4-1,8-1公式)
If she had worked harder, she would have succeeded.
The rice would not have been burnt if you had been more careful.
If my lawyer had been here last Saturday, he would have prevented me from going.
④、混合条件句
主句与从句的动作发生在不同的时间，这时主句和从句谓语动词的虚拟语态形式因时间不同而不同，这叫做混合条件句。
If you had asked him yesterday, you would know what to do now.
（从句与过去事实相反，主句与现在事实相反。）
If it had rained last night (过去), it would be very cold today (现在).
If you hadn't watched TV yesterday, you wouldn't be so sleepy now.
如果你昨天不看电视，你现在也就不会这么困了。
(从句yesterday说明过去，主句now说明现在)
⑤、含蓄条件句
非真实条件句中的条件从句有时不表达出来，只暗含在上下文中，这种句子叫做含蓄条件句。含蓄条件句大体有三种情况：
A、条件暗含在短语中
He would not get such a result without your help.
(条件暗含在介词短语without your help中)没有你的帮助，他就不会有今天的成果。
But for you, I could not be recovered so soon.
(条件暗含在But for you中)要不是有你，我就不会恢复得这么快。
This same thing, happening in the past, would lead to a disaster.
(条件暗含在动词-ing形式短语happening in the past中)
同样的事，如发生在过去，就会酿成大祸。
He must have been there, or he never could know the place so well.
(暗含条件是连词or)他一定是去过那儿，否则他绝不会对那个地方如此熟悉。
B、条件可根据上下文推理出
It would do you no good.
(条件可能是if you should give up the job如果你放弃这项工作的话)
这可能会对你没好处。
They could have won.
(条件可能是if they had been patient如果他们有耐心的话)他们本来是会赢的。
Such mistakes could have been avoided.
(条件可能是if you had been more careful如果你更加小心一点的话)
这种错误完全能避免。
Why didn't you tell me about it? I should have helped you.
(条件可能是if you had told me about it如果你当时告诉我的话)
为什么你不告诉我？我会帮助你的。
－Did you go to see him yesterday? 你昨天去看他了吗？
－I would have, but someone dropped over to my house for a visit.
(条件是if no one had dropped over to my house for a visit如果没人到我家来玩的话)
原想去的，但有人到我家来玩了。
C、条件用其他形式来表示
She was ill, otherwise she would have been present at the meeting.
(条件通过连词otherwise/or表示出来：If she had not been ill...)
她病了，否则的话就会出席会议了。
I told him to go there himself, but perhaps I should have gone together with him.
(连词but暗示条件) 我让他自己去那里，但也许我应该和他一道去。
Suppose you were in my shoes, what would you do?
(用suppose/supposing/providing等词表示if)假若你站在我的立场上，你会怎么办？
To talk with her, you would know she could not hear well.
(to v短语带有假设的意思，相当于If you should talk with her...)
如果你同她交谈，你就会知道她的听力不好。
Left to himself, he could not have finished the work.
(v-ed形式表示条件：If he had been left to himself...)
要是放任他的话，他是不可能完成工作的。
提示：
a、在很多情况下，虚拟式已变成习惯说法，很难找出其暗含的条件。
You wouldn't know.你不会知道。
I would like to go with you.我愿意和你一起去。
b、be going to / will用于条件句时，be going to表将来，will表意愿。
If you are going to make a journey, you'd better get ready for it as soon as possible.
Now if you will take off your clothes, we will fit the new clothes on you in front of the mirror.
3)、虚拟语态的其他用法
除主要用于非真实条件句外，还可用在部分主语从句、宾语从句、表语从句、同位语从句、定语从句和状语从句之中。
(1)、名词性从句中的虚拟语态
主句中的动词、名词、形容词如果表示要求、建议、命令或愿望等含义，与其相关的名词性从句(主语从句、宾语从句、表语从句和同位语从句)中的谓语动词要用虚拟语态。
①、主语从句中的虚拟语态
主语从句通常用于"It is + 形容词/名词/v-ed形式+that..."结构。主语从句中是否用虚拟语态取决于所用的形容词、名词或v-ed形式，其谓语动词常用"should + 动词原形"(美国英语常省略should，只用动词原形)。
句型：
(a)suggested
It is (b)important that…+ (should) do
(c)a pity
A、表示建议或命令
It is important and necessary that we (should) keep the balance of nature.
我们要维持生态平衡，这是重要而且必不可少的。
It is necessary that the program (should) be loaded into the computer.
有必要把程序输入电脑。
It will be better that we (should) meet some other time.最好我们在另一个时间见面。
It is suggested that each student (should) sing a song in English.
有人建议每个学生都要唱一首英文歌曲。
It is demanded that he should leave at once.要求他立刻离开。
It is desired that we (should) get everything ready by tonight.
希望一切在今晚前准备就绪。
B、表示惊讶
It is strange that he (should) have failed to see his own shortcomings.
真奇怪他竟看不到自己的缺点。
It is strange that he should have learned so much in such a short time.
很奇怪他竟然在如此短的时间内学了那么多的东西。
It is a pity/shame that I (should) be at school instead of lying here in hospital.
真可惜，我应当在学校而不是躺在医院里。
It is a pity that you (should) miss such a good chance.
真遗憾你竟然失去这么好的机会。
It is natural that you (should) forget it first.你起先记不住是很自然的。
必背：常见的要接含有虚拟语态主语从句的词
形容词：important, necessary, urgent(紧急的,急切的), essential(完全必要的,本质的), vital(必不可少的；生命的), natural, strange, funny, surprising,proper等
v-ed形式：arranged, suggested, ordered, required, desired, demanded, proposed,
requested,insisted等
名词：a pity, a shame, no wonder等(表达说话者的感情色彩)
