had better前能否用情态动词

用情态动词should,shouldn't,have to,had better,had better not,must 请问had better是情态动词吗 you had better be careful.had better 的词性是情态动词,be careful词性是名 had better是情态动词吗?他的否定和疑问句如何构成? need能否做情态动词? 1.we had better be careful.为什麽这里用be,而不是are?是因为had better 是情态 You had better+动词原形 祈使句能否以情态动词开头? you had better 是后面加动词ing形式或者加动词原形还是加to在动词前? had better 后的动词用什么形式 pick前用的是什么动词（be动词、助动词、情态动词） 情态动词怎么用?