need to do sth.可以用于否定句或疑问句中吗?need do sth.可以用于肯定句中吗?就是说有没有“Do we need to come tomorrow?”、“I need come there tomorrow.”、“I need come there tomorrow.”刚才打错了，有没有You needn't to come tomorrow.

如果need 是实义动词，即需要什么东西时，使用don't need
如果是情态动词，就用needn't

need to do sth.可以用于否定句或疑问句中,这里need 是实义动词.need do sth.可以用于肯定句中,这里need是情态动词.
不说Do we need to come tomorrow?而说Will we need to come tomorrow?这里need 是实义动词.
可以说I need come there tomorrow.这里need是情态动词.

need 可做情态动词，也可做实物动词，做情态动词时，后面跟动词原形，need do sth；做实物动词时，后面跟to do 或 doing，上一答复例句中为实物动词。可以用于need否定和疑问。

Do we need to come tomorrow?
i need to come there tomorrow.
You needn't come tomorrow.

need 1.首先是个实义动词,可以用于任何句式Do we need to come tomorrow?”正确2.need也可用做情态动词,但只能用于否定句疑问句和条件从句中I need come there tomorrow不对,应在need后加 to.You needn't to come to...

只能用于否定句

可以，Do we need to come tomorrow?是need做实义动词；I need come there tomorrow。是做情态动词。