在622M复用段保护环中参与保护倒换的单板有（）。
A.交叉板
B.线路板
C.支路板
D.主控板
参考答案：A, B, D
We don't care if a hunting dog smells _______, but we really don't want him to smell _______.
A．well; well
B．bad; bad
C．well; badly
D．badly; bad
