have to后面加什么形式

　　We may have to take military action.

　　我們可能不得不采取軍事行動。

　　We have to set a time limit for the work.

　　我們得為這項(xiàng)工作規(guī)定個(gè)期限。

　　Now she won't have to go out to work any more.

　　現(xiàn)在她不必再出去工作了。

　　I'd love to come, only I have to work.

　　我很想去，但是我要上班。