need作情態動詞時，只在否定句和疑問句的情況下，後跟動詞原形，這時候沒有人稱和數的變化。以need作情態動詞時的一般疑問句，回答是Yes, ... must/... have to. No, ... needn"t.
如：Need I clean my room? Yes, you must/you have to. No, you needn"t.
You needn"t do your homework. He needn"t take a taxi.
need作實意動詞時，有人稱和數的變化，用法結構為① need sth. ② need to do sth.
在疑問句和否定句中也是有實意動詞情況的，這時候用法和其它的實意動詞一樣，否定句和疑問句需要助動詞來完成，但不能脫離它作為實意動詞的結構。
如：You don"t need some water. You don"t need to take a walk.
She doesn"t need a cup of tea. She doesn"t need to take some medicine.
Do you need a pen? Does it need to clean?
Which book does he need? What do you need to know?
need作情態動詞時，只在否定句和疑問句的情況下，後跟動詞原形，這時候沒有人稱和數的變化。以need作情態動詞時的一般疑問句，回答是Yes, ... must/... have to. No, ... needn"t.
如：Need I clean my room? Yes, you must/you have to. No, you needn"t.
You needn"t do your homework. He needn"t take a taxi.
need作實意動詞時，有人稱和數的變化，用法結構為① need sth. ② need to do sth.
在疑問句和否定句中也是有實意動詞情況的，這時候用法和其它的實意動詞一樣，否定句和疑問句需要助動詞來完成，但不能脫離它作為實意動詞的結構。
如：You don"t need some water. You don"t need to take a walk.
She doesn"t need a cup of tea. She doesn"t need to take some medicine.
Do you need a pen? Does it need to clean?
Which book does he need? What do you need to know?