521.Let's learn to use the problem we are facing _______ a stepping stone to future success.
A.by nature
B.in return
C.in case
D.by chance
522.Modern equipment and no smoking are two of the things I like _____ working here.
A.with
B.over
C.at
D.about
521.答案是C;
use…as a stepping stone to future success.把…当作通往成功的阶梯。
522.答案是D;
句意:关于在这里工作,我喜欢的两件事情是现代化设备和禁止吸烟。