问题补充：
—Mei will represent our class in the English Speech Contest.
—She is clever and can speak English really well. She will not make us disappointed
A. knock into us
B. care about us
C. let us down
D. help us out
答案：
(答案→)A. knock into us
B. care about us
C. let us down
D. help us out
解析： 略
