情态动词语法高中的,

问题描述：

情态动词语法高中的,
1.she hasn't turned up so far.what __ have happened to her
A,can B may
c,should,D must
2.why __ it get colder when wo go up a mountain?
A,should B would
C must
3.dare u go out at night?
A yes,i do B no i dare not
C no i don't Dyes i dare to
4.you needn't do the job at once,needn't you?
yes i'm afraid i __
A need B needn't
C must D musn't