《咳论》指出六腑咳应当取五俞穴中的什么穴刺治（）
A.井穴
B.荥宋
C.俞穴（原穴）
D.经穴
E.合穴
参考答案：E
---Sorry, sir. I can't answer this question.
---Well, you are supposed ______ this part of history.
A．reading
B．to be reading
C．to read
D．to have read.
请你说明什么是清洁提单和不清洁提单
