We have to at the hotel before 6 pm.A check onB c

Have you checked（)at the hotel yet？A、inB、outC、up

We have decided to call ______ Mr. Black sometime next week at his home.A．onB．atC．upD．for

We could have walked to the station. It was so near. A taxi______at all necessary.A．wasn"t

Everyone should______before he / she stays at a hotel in the United States.A．check upB．che

Ask them to______ carefully the planes radio and radar system.A．check onB．check offC．check

It is really quite extraordinary that we______at the same college without having met befor