[语法初识]
[语法剖析]
1．用作实义动词
(1) 有人称和数的变化，其第三人称单数形式为needs，变为否定句或疑问句时要用助动词do/does/did。

(2)后跟名词、代词、不定式或动名词作宾语，当need的主语与need后面的动词之间是被动关系时，need后面接不定式的被动形式或动名词的主动形式。

You don't need to worry about me.
你不必担心我。

The room needs cleaning/to be cleaned, but I only have time on Sunday.
房间需要打扫，但是我只有星期天有空。

2．用作情态动词
(1)need表示“需要”或“必须”，通常用于否定句和疑问句。

You needn't do it again.
你不必再做了。

Need he do his homework first?
他需要先做作业吗？
(2)由must引起的一般疑问句中，否定答语可用needn't, 意为“没必要”。

—Must I do the work now?
—No, you needn't.
——我现在必须做这项工作吗？
——不，你不必。

(3)在need引起的一般疑问句中，肯定回答用must，否定回答用needn't。

—Need I go there too?
—Yes, you must./No, you needn't.
——我也需要去那儿吗？
——是的，你必须去。

/不，你不必去。

集中演练1
1－1.单句改错
①—I'm sorry I will be very busy tomorrow.
—If so, you didn't need to come.didn't need to→needn't
②As a result of the serious flood, two thirds of the buildings in the area need repair.repair→repairing/to be repaired
③—Must I hand in the paper before Friday?
—No, you mustn't.mustn't→needn't
④I couldn't use a clock to wake me up every morning because I am always woken up by my mother.
couldn't→needn't
1－2.完成句子
⑤Dr. Smith needed (需要) no payment for his work.。