开关、避雷器、架空地线接地电阻值不应大于（）Ω。
A.7
B.8
C.9
D.10
参考答案：D
痹证的病理主要是（）
A.素体阳虚，阳气不得布达周身
B.素体阴虚，阴血无以濡养筋络
C.气血为病邪阻闭，运行不畅
D.素体气虚，无力推动气血运行
E.以上均非
I’m surprised that he _____ in the exam.
A．should fail
B．would have failed
C．may have failed
D．should have failed
