A． upB． offC． downD． over

The police need your help to（)the murderer.A look upB look forC track downD try out

We shouldn’t（) those people who need our help urgently.A sit upB sit forC sit downD sit

在按钮编辑模式中，以下各帧中哪一个是鼠标按下时的状态？（)A.UpB.OverC.DownD.Hit

【B20】A．broken upB．broken offC．broken awayD．broken down

【C10】A．give upB．give offC．give outD．send off

【C9】A．speeds upB．acceleratesC．slows downD．goes down