要快,急!!!!!!!!!
第1个回答 2009-02-04
must:
1)表示必须必要
You must come in time.
回答must引出的问句时,如果是否定的,不能用mustn't,而是要用needn't或don't have to。如
——Must we hand in our exercise books today?
——Yes, you must.
——No, you don't have to (you needn't).
2)must+be+表语的结构表示有把握的推测,他的否定或疑问形式用can代替must。如:
This must be your pen.
need:
1)表示“需要”或“必须”,做情态动词用时,仅用于否定句或疑问句。在肯定句中一般用must, have to, ought to 或should 代替。如
-Need I finish the work today?
-Yes, you must.
2)作实意动词时,又人称、时态和数的变化。
They did not need to arrive so early.本回答被提问者采纳
1)表示必须必要
You must come in time.
回答must引出的问句时,如果是否定的,不能用mustn't,而是要用needn't或don't have to。如
——Must we hand in our exercise books today?
——Yes, you must.
——No, you don't have to (you needn't).
2)must+be+表语的结构表示有把握的推测,他的否定或疑问形式用can代替must。如:
This must be your pen.
need:
1)表示“需要”或“必须”,做情态动词用时,仅用于否定句或疑问句。在肯定句中一般用must, have to, ought to 或should 代替。如
-Need I finish the work today?
-Yes, you must.
2)作实意动词时,又人称、时态和数的变化。
They did not need to arrive so early.本回答被提问者采纳
第2个回答 2009-02-04
need 有主观意愿
must 别人强迫
例如说:i need to do my homework (表达说话人主观上要做也不得不做)
you have to do your homework(表达说话人让‘YOU’必须去做,不得不做,但‘YOU“不一定想做的事)
must 别人强迫
例如说:i need to do my homework (表达说话人主观上要做也不得不做)
you have to do your homework(表达说话人让‘YOU’必须去做,不得不做,但‘YOU“不一定想做的事)
第3个回答 2009-02-04
主要是口气不同。事态较严重用must。(口气较重)