采煤机检修后截割部应进行（）跑合试验和加载试验。
A、压力
B、轻载
C、连续
D、重载
参考答案：B
网络安全的基本要素中，______是指确保信息不暴露给未授权的实体和进程。
The teacher spoke so fast that it was hard for the students to（）what he was saying.
A. take in
B. take off
C. take on
D. take after
