热媒循环泵切换检修完成后，应该（）出口阀的旁通阀，使泵处于备用状态。
A、拆下
B、关闭
C、打开
D、50%打开
参考答案：C
--- Why was Mr. Li so happy this morning?
--- Because he was honoured with a(n) _____ for excellence in teaching.
A．present
B．gift
C．award
D．reward
珊瑚的横截面呈（）
A.波纹状
B.同心圆构造
C.平行花纹状
D.勒兹纹状
