特种爆破包括()等。
A、爆炸加工
B、聚能爆破
C、油气井爆破
D、地震勘探爆破
参考答案:A, B, C, D
We are _________ Christmas lights.[ ]
A. buy
B. buying
C. to buy
D. buying to
半解剖式人工牙的牙尖斜度是()
A.10°
B.15°
C.20°
D.25°
E.30°