请解释英语和中文中的语法和词性答:is there a firm on tonight? 但这只限少数动词,如begin,come,go,leave,sail,start,arrive,return,dine,end,stop,depart,open,close,be等。另外,在时间或条件从句中,将来动作或状态多用这一时态表示: tell her about that when she come。 turn off the light before you leave。 we‘ll start as soon ...