need的用法
• 表示“需要”时为实意动词，后面可以加名词，也可以加不定式：
I need a pen.
Do you need any beer? No, I don’t.
I need to have a rest.
Need doing=need to be done （表示被动）
The flowers need watering. =The flowers need to be watered. 花需要浇水。
• need在否定时做情态动词使用：
You needn’t go so early. (=You don’t need to go so early.)
Must I clean the desk right now? No, you needn’t.