need 与dare ，它们既可以作情态动词又可作实义动词。
1．Need 作情态动词使用时，没有人称、数和时态的变化，一般使用于否定句和疑问句中。
1) He need not come at once.
2) Need he come at once?
3) Need you do the thing right now?
------Yes ,I must.
------No ,I needn’t.
4) He said (that) he need not obey orders.
情态动词need可用于下列形式：
a) 可与完成式连用表示：（过去）本来不需做的而做了。例如：You needn’t have bought it. /
You needn’t have gone there yesterday.
b) 情态动词need 可以用于进行时。例：We needn’t be standing here in the rain.
c) 情态动词need 可用于被动式。例：She needn’t be told ,we should keep it secret from her. /
They needn’t have been punished so severely.
２．Need 作实义动词时是及物动词，与实义动词一样有人称、数和时态的变化，其后可以跟名词、代词、不定式、动名词及复合结构等。例：
1) The old man needs your help.
2) You don’t need to go to there.
3) Does she need to read English in the morning?
4) Do you think you will need any new equipment?
5) The garden needs watering.
6) The garden needs to be watered.
7) I need you to help me with my English.
３．Dare作情态动词和作情态动词的need 变化相似，没有人称、数的变化，表示意志上的主观可能，指在勇气和胆量上可能。一般可用于否定句、疑问句和条件状语从句中，在美式英语中尤其如此，一般不用于肯定句中。例：
1) He dare not go out at night.
2) They dare not express their views boldly.
3) How dare you say such things against them?
4) Dare you go home alone?
5) If the aggressors dare come ,they will never be able to get away.
但I dare say是惯用语，意为“我想、在我看来、大概、恐怕”等。例：
I dare say the leader would give you leave.
I dare say it will be rainy tomorrow.
情态动词dare 可用于完成式表示过去时间，例：
I dare not have gone to Shanghai alone last year ,but I think I dare now.
She has never dared to tell her mother that thing.
4．Dare作实义动词和实义动词变化相同，有人称、数和时态的变化。
1) She dares to answer these questions.
2) We should dare to think , speak and do.
3) Do you dare to touch the snake?
4) She said she dared.
5) He never dare to come here.
6) You should do it if you dare.
7) She lied on the bed , not daring to make a noise.
8) I didn't know that how he dared to drive a car.
[示例]
考题1 No one ____ say that he could see the Emperor’s new dothes.
A. dare B. Needs C. Dared to D. need to
解析 根据提干要求表示过去的情况即那时没有人有胆量敢说他没看见皇帝的新衣裳，因此应选Ｃ，因dare表示过去式是实义动词才合乎题意。
考题２ You ____ bring many books back until next month.
A. need to B. Dare to C. Dare not D. needn’t
分析 据题旨意，句子后用了until介词＋时间的介词短语作时间状语，那么前面的动词bring是终止性动词应使用否定式表示没必要，而dare not意为不敢，不合题意，所以正确答案是Ｄ。
考题３ Tom wanted me to play truant this afternoon with him ,but I ____ do so.
A. dared not B. Didn’t dare to C. Not dare D. dare not
分析 据该题意也是说过去的情况，在Ａ项中dare作为情态动词不能用过去式，Ｃ和Ｄ项均不合题意。答案Ｂ，是表示过去式，dare在这里作为实义动词前面用助动词的过去，后面to 可以跟不定式，可断定适合题意，所以该题答案选Ｂ。
考题４ Father sent me the book , so I ____ to him for it.
A. needn’t write B. Needn’t have written
C. dare not write D. dare not have written
分析 据题意：父亲把书寄来了，我本没必要给他写信，但信已写了。所以该选项的Ｂ答案，此答案needn’t接动词的完成式表示过去本来没必要做的事，而做了，所以与该题达意。
［训练］
1. You must pay the money , but you ____ do so at once.
A. mustn’t B. Dare not C. Needn’t D. don’t need.
2. You ____ try it again.
A.. needn’t to B. Needs C. Needn’t D. didn’t need
3. I wonder if he ____ wait any longer.
A. need B. Needs C. Need to D. doesn’t need
4. She ____ kill the snake . She is afraid of it.
A. doesn’t dare B. Dares not to C. Dare not D. dare to
5. Being scolded by the teacher , the boy stood before him without ____ his head.
A. daring lift B. Daring to lift C. Daring lifting D. dare to lift
