Question

—Where did you get The Frog written by Mo Yan?
—I picked it up from a bookshop online if you ________ know.

A．must	B．will
C．can	D．shall

Answer 1

A

A 考察情态动词，句义：如果你非要知道，我是在网店里买到的这本书。Must表示非得，偏要。