问题补充:
—Where did you get this book?
—I picked it up from a second-hand bookshop if you know.
A. must
B. will
C. can
D. shall
答案:
(答案→)A. must
B. will
C. can
D. shall
解析:A. must必须,一定 B. will将要 C. can能够 D. shall将要;句意:你从哪里得到这本书的?如果你一定要知道的话,我是从二手书店买的。故选A