金属基底冠预氧化后,表面被污染易导致金瓷修复体A.瓷表面出现裂纹 B.瓷层内出现气泡 发布时间:2018-07-22 15:35 │ 来源:www.tikuol.com 题型:单项选择题 问题: 金属基底冠预氧化后,表面被污染易导致金瓷修复体A.瓷表面出现裂纹B.瓷层内出现气泡C.色泽不佳D.瓷收缩率增大E.金属氧化膜过厚
题型:单项选择题 At the conference, political leaders from many countries promised to work together to defend the world _____ terrorism and other threats. [ ]A. for B. without C. beyond D. against 查看答案