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2008-08-10 21:30:49
10)、dare
dare既可用做能愿助动词，也可用做行为动词，指勇气和胆量上的可能，可译为“敢”。
(1)、能愿助动词dare
①、dare作为能愿助动词时主要用于疑问句和否定句中，一般不用于肯定句中。
－Dare you walk through the forest at night? 你敢在黑夜穿过森林吗？
－Yes, I dare. 是的，我敢。
－No, I daren't. 不，我不敢。
He dare not drive too fast on the rainy day.下雨天他不敢开得太快。
He dared not do it last year.去年他不敢做这事。 (dare的过去时为dared)
②、可以用于表示怀疑的名词性从句中。
I wonder how he dare say such things.我真奇怪他怎么敢说出这们的话。
We don't know whether he dare climb the mountain.我们不知道他是否敢爬那座山。
③、可以用于(真实)条件状语从句中。
If the enemy dare enter the village, we'll fight against them to the end.
如果敌人敢进入村里，我们就和他们战斗到底。
If you dare cheat in your exam, I will give you some punishment.
如果你们敢在考试中做弊，我就惩罚你们。
(2)、行为动词dare
①、dare可以作为行为动词，多用于肯定句中，但也可用在疑问句和否定句中。
He will dare any danger.他敢面对任何危险。
He dared me to jump over the stream.他激我跳过小溪。
Did anyone dare to admit it? 有人敢于承认吗？
I have never dared (to) go back to take a look.
我再也不敢返回去看一眼了。(否定句中to可省略)
②、和其他行为动词一样，dare在句子中要随着主语的人称和数发生变化。
He doesn't dare to walk at night.他不敢走夜路。(做行为动词)
He daren't walk at night.他不敢走夜路(做能愿助动词)
Does he dare to walk at night? 他敢走夜路吗？(做行为动词)
Dare he walk at night? 他敢走夜路吗？(做能愿助动词)
Will you dare to do the same experiment tomorrow?
明天你敢做同样的实验吗？ (做行为动词)
Dare you do the same experiment tomorrow? 明天你敢做同样的实验吗？
必背：英语口语中dare的几个常用结构：
A、I dare say...我想，大概，可能，或许……
I dare say things will improve. 我想情况会好转的。
B、How dare you ...? 你怎么敢……？
How dare you ask me such a question? 你怎么敢问我这样的问题？
C、I dare you ... 我谅你也不敢……
I dare you to tell your parents! 我谅你也不敢告诉你父母！
11)、need
(1)、能愿助动词need
need和dare一样，作为能愿助动词时，主要用于否定句和疑问句，一般不用于肯定句中(在肯定句中常被must, have to, ought to, should等能愿助动词取代)。作为能愿助动词，它的词形只有need一种形式。
You needn't return the book now. You can keep it till next week if you like.
你现在不必还书，如果愿意，你可以下周还。(needn't = don't have to)
Need I hand in my homework now? 我现在就要交家庭做业吗？
－Need he finish the article next week?他要下个星期完成这篇文章吗？
－Yes, he must.是的，他必须完成。
－No, he needn't.不，他不需要。(= he doesn't have to)
(2)、行为动词need
need和dare一样，也可以做行为动词，可用于肯定句、否定句和疑问句中。行为动词need有人称和数的变化。
My shirt needs a button. 我的衬衫需要一枚钮扣。
Your car needs repairing.你的车该修理了。
He has grown up. We don't need to worry about him.
他已经长大了，我们不必为他担心。
You don't need to buy so many things for the picnic.你不必为这次野餐买这么多东西。
Patience is needed for that job.干那工作，需要耐心。
比较need和dare
作为能愿助动词，两者都只能用于疑问句，否定句和条件句。need做实义动词时后面的to v短语必须带to，而dare做实义动词用时, 后面的to 时常可以被省略。
A、实义动词“need（需要, 要求）”：need + n. / to do sth
B、能愿助动词“need”：只用原形need后加do，否定形式为need not。
Need you go yet?
Yes, I must. / No, I needn't.
C、need 的被动含义：同want,require,worth(形容词)三词一样，need后面接doing也可以表示被动。即：need doing = need to be done
复习：
will既可当做将来、能愿助动词，表请求、建议等，也可作为实义动词表"意愿、意志、决心"；wouldn't(将不,不会的)；needn't(不必,不用)；mustn't(禁止,不能)；shouldn't(不应该)；
will 与you连用，用来提出要求或下命令；should与you 连用，用来提出劝告。
---Shall I tell John about it?
---No, you _ needn't __. I've told him already.
---Don't forget to come to my birthday party tomorrow.
---___ I won't ___.
12)、将来、能愿助动词+动词完成式
"将来、能愿助动词 + have done"是一个十分重要的结构，这种结构有两个主要的用法。
(1)、表示对过去发生动作或状态的推测或估计
|
May/might have done |
表示“大概已经” |
通常用于肯定句和否定句。might有时可用于疑问句。 |
|
can/could have done |
表示“可能已经” |
通常用于疑问句和否定句。could有时可用于肯定句。 |
|
Must have done |
表示“一定已经” |
只用于肯定句，具有较大的可能性 。 |
|
should have done |
表示“该” |
可能性较小。 |
①、may/might have done表示对过去事实不大肯定的推测，常译为“大概已经”。
They might have taken a later train.也许他们乘坐的是晚一点儿的火车。
He seems to know the city quite well. He may have been there before.
他似乎对那个城市很熟悉，他以前可能去过那儿。
Philip may (might) have been hurt seriously in the car accident.
②、can/could have done表示对过去事实的推测，常用于否定句和疑问句。
He can't/couldn't have watched TV yesterday for he knew they would have an exam.
昨天他不可能看电视，因为他知道快要考试了。
I don't know why she didn't call me yesterday. Can/Could she have forgotten my telephone number?
我不知道昨天她为什么没给我打电话，难道她会把我的电话号码忘了吗？
Philip can (could) have been hurt seriously in the car accident.
③、must have done
表示对过去事实有把握的推测，具有较大的可能性。语气较强，具有"肯定"，"谅必"的意思。只用于肯定句中，否定句和疑问句用can/could have done。
His watch must have stopped.他的表肯定停了。
－I rang your flat yesterday. A man answered but I didn't recognize the voice.
昨天我给你家打电话，一位男士接了电话，但我没听出来是谁的声音。
－Oh, it must have been my brother Peter.哦，那一定是我哥哥彼得。
---Linda has gone to work, but her bicycle is still here.
---She must have gone by bus.
(2)、表示对过去发生动作的遗憾或责备
|
might have done |
表示“本可以” |
通常用于肯定句。 |
|
could have done |
表示“本可以” |
通常用于肯定句。 |
|
should have done |
表示“应该” |
可用于肯定句、否定句和疑问句。 |
|
ought to have done |
表示“应该” |
同should have done。 |
|
needn't have done |
表示“本没有必要” |
只用于否定句。 |
①、might have done表示“本来应该或可以做但没有做某事”，含有轻微的责备口吻或遗憾。
You might have given him more help, though you were busy.
你本来应该给他更多的帮助，虽然你很忙。
The proposal might have been refused.这个建议本该拒绝的。
②、could have done可表示”对过去能做而未做的事感到惋惜、遗憾”，可译成“本来是可以……的”。
Why didn't Sophie apply for the job? She could have got it.
为什么索菲不申请这项工作？她本来是能得到的。
Why did you stay at a hotel when you went to
③、needn't have done表示“没有必要做某事，可是事实上做了”，用于对过去的责备。
I dressed very warmly for the trip, but I needn't have done so. The weather was hot.
John went to the station with the car to meet Mary, so she needn't have walked back home.(Mary步行回家，没有遇上John的车。)
约翰开车去车站接玛丽，所以她本不必步行回家了。
The airport is close to us. You needn't have hurried there early.
机场离这儿很近，你没必要早早地赶到那里。 (可是你早早地到那儿了)
He is still young. You needn't have sent him such an expensive present.
他还小，你没必要送他这么昂贵的礼物。
提示：如表示“过去不必做也没有做”之意，需用didn't need to do。
I know the airport is close to us. I didn't need to hurry there early.
我知道机场离这儿很近，因此我也没必要早早地赶到那里。(实际上也没早到那儿)
It is not cold today. I didn't need to take the thick sweaters out.
今天天气不冷，我没有必要把厚毛衣拿出来。(实际上也没拿)
④、should/ought to have done本应该做某事，而事实上并没有做。否定句表示"不该做某事而做了"。表示对过去动作的责任或批评。ought to 在语气上比should 要强。
You ought to (should) have been more careful in this experiment.
He ought not to have thrown the old clothes away.（事实上已扔了。）
You should have gone over your lessons.你们应把功课复习好的。(可事实上你们没有。)
You shouldn't have watched TV last night. 你们昨天晚上本不该看电视。(可你们看了。)
You oughtn't to have gone to the deserted place alone.你不该独自去那荒凉之地。
