初二英语选择,急.1.They were so frightened that they ran ________the

初二英语选择,急.
1.They were so frightened that they ran ________the woods as fast as possible.
A.through
B.cross
C.though
D.across
2.You 've just had lunch.You____be hungry now.
A.can't
B.mustn't
C.may not
D.must
3.--May I leave work early today as I have to go to the dentist's?
---Yes,you______.
A.can
B.must
C.may
D.need