谁告诉我need的用法

问题描述:

谁告诉我need的用法
i need some money ____(buy) a gift for your family.
need i ____(write) his name here?
the flowers need ____(water).
遇到这种题目,怎么去思考这时候是属于情态动词还是行为动词噢?

need 作为情态动词时,后加动词原形,多用在疑问句和否定句里.
而need作为实义动词时后加动词要用不定式,用在肯定句里.