问题补充：
Mother: Bob is sure tonigh.
Father: Don be so sure it.
A. to come ; about
B. to come; of
C. will come; for
D. coming; with
答案：
A. to come ; about
(答案→)B. to come; of
C. will come; for
D. coming; with
解析：be sure to do sth. 一定, 必然; be sure of/ about…确信, 有把握.
