you'd better ask the policeman---ask后加介词吗?

you'd better ask the policeman---ask后加介词吗? I dont know the 什么 .you may ask the policeman You can ask the nearby policeman for help. You 'd better ask him to show you the way to the hotel.改为祈使句 when visitors ask you the way, you'd better tell them po____ If you don't want to get lost,you'd better ask for the way.那 before seeing the doctor ,you'd better ask the nurse to take I don't think him_______ the work.You'd better ask somebody Don't climb the mountain a___. You'd better ask some friends Kate ,you 'd better ask the teacher ___(有反身代词填空) You'd better ___(ask)him the question 被动语态的题怎么做啊 You‘d better ask the professor for more advice on your studi