According to the air traffic rules, you ___ switch off your mobile phone before boarding.
A．may B．can C．would D．shall
— Do you think another Korean War will break out?
— Only through peaceful dialogues can a war be avoided.
A．No way. B．That’s for sure C．Why not? D．It depends.
While studying， fix your mind on what is really important， or you will
remembering nothing.
A．take up B．lead to C．stick to D．end up
Advertising is different from other forms of communication in that the advertiser pays for the message .
A．to deliver B．having delivered C．to be delivered D．delivering
— Hi，Michelle， I can’t find my e-dictionary.
— Sorry，I it. I guess I put it on the top shelf with my things.
A．had used B．used C．was using D．am using
－Do you know why Michael resigned from the board?
－He held out for higher wages, but was ____ in the end.
A．put down B．broke down C．cut down D．turned down
