Whose magazine is this?
It ______ be Nancy' s. Look! Her name is on its cover(封面).( )
must
can't
mustn't
Eighty percent of the students in this school______three to five times a week.( )
exercises.
exercise
exercising
That ______be an alien﹣there's no such thing!( )
might
Miss Li likes swimming very much and now she_______ on Saturday afternoon.( )
used to swim
is used to swim
is used to swimming
If you take a vacation this summer,so______I.( )
will
do
am
________have you prepared for the competition?
For two months.( )
How far
How long
How soon