英语动词有两种语态,主动语态和被动语态。主动语态表示主语是动作的执行者,被动语态表示主语是动作的承受者。如:
They will build a new bridge over the river. (主动)
A new bridge will be built over the river. (被动)
They will build a new bridge over the river. (主动)
A new bridge will be built over the river. (被动)