Lf you are busy,you ___come to attend the meeting.

问题描述:

Lf you are busy,you ___come to attend the meeting.
a/mustn't b/ needn't c/ can't d/ have to
不明白此句的语气应该用哪个词来修饰、

b/ needn't
整句的意思是:如果你忙,你可以不来参加聚会.