Question

—Will you stay for some more days?
—Sorry, I_____. My mother called to ask me to go back at once.

A．mustn’t

B．may not

C．can’t

D．wouldn’t

Answer 1

C

情态动词表推测。句意：－你再呆几天好吗？－对不起，我不能，我的母亲打电话让我马上回去。Mustn’t禁止；may not可能不；wouldn’t不愿做……，将要不……。故选C。