___ was announced,everybody must finished their work before

___ was announced,everybody must finished their work before The clock was beginning ___ twelve and everybody held their They must finish their work before lunch 改为否定句 the work must be finished before five o'clock,___you may go pleace they must have finished their work by now.为什么用have fi You must first be finished before lunch. Everybody does their own work well. They must have finished their homework,_______. Must we finishe the work before five?No,you ___.You can do i The work was finished sooner than e_____ ____ he ___ go to work by ferry before the bridge was built? everybody,finish your home work before you p