滑脉的脉象特点是（）
A.沉取即得
B.往来流利，
C.三部寻按有力
D.来盛去衰
E.如轻刀刮竹
参考答案：B
— What do you think of your new English teacher?
— She was well prepared for her first lesson and left us a good ______. [ ]
A. expression
B. instruction
C. appearance
D. impression
通过除雾器的烟气流速越高，（）。
A、除雾器的效率也越高
B、越不利于液滴的分离
C、越容易堵塞结垢
D、越容易造成烟气的二次带水
