进行二尖瓣替换手术时，容易损伤哪支冠状动脉（）
A.右冠状动脉
B.对角支
C.前降支
D.回旋支
E.左冠状动脉主干
参考答案：D
Our English teacher is very strict us and____ his teaching. [ ]
A. with; on
B. with; in
C. to; on
D. to;in
刀具齿槽铣削后，对其几何形状的检验内容有前角、后角、齿深、齿形、及等距性等。
