氧化锌丁香油水门汀的性能特点是:()
A.是热和电的绝缘体,对牙髓无害
B.溶于唾液
C.弹性模量和银汞合金相似
D.足以承受银汞合金压力
参考答案:A
Mrs. White found her husband surrounded by letters and papers and _____ very worried. [ ]
A. look
B. looks
C. looking
D. to look
工艺是指产品的制造的()和()。