My brother with other nine firefighters ______ hard every day in order to help people in need at any time.( )
A.practicesB.practiceC.practiced
I like Chinese, _______ I don't like math, because it's not easy to learn it well.( )
A.andB.butC.or
I think it's impolite _______ others waiting.( )
A.to keepB.keepingC.keep
I cleaned my room yesterday. It _______ a little difficult.( )
A.isB.wasC.will be
Mountain climbing is one of _______ sports in the world.( )
A.dangerousB.more dangerous
C.the most dangerous
Are these your books?
No, they aren't. They are _______.( )
A.sheB.hersC.her