断面较平坦，粉性的中药材是（）
A.黄柏
B.牡丹皮
C.厚朴
D.肉桂
E.杜仲
参考答案：B
He decided to ____ the job after he quarreled with the manager. [ ]
A. stop
B. block
C. loosen
D. quit
单纯锅内水处理的优点有哪些？
