传统的输精管吻合术放置支架可选用下列哪些材料（）
A.尼龙线
B.金属线
C.动物毛
D.丝线
E.细管状物
参考答案：A, B, C, D, E
I really don’t know _____ I put my wallet after I paid the bill.
A．where was it
B．it was where that
C．where it was that
D．where was it that.
有关防水混凝土结构施工缝留置，正确的说法是（）。
A.应留在变形缝处
B.留在剪力最大处
C.留在底板与侧壁交接处
D.留在任意位置都可
