著作权自作品发表之日起产生。( )
参考答案：错
患者男性，邻面龋坏，检查：见邻面接触点破坏，拟行邻嵌体修复
关于嵌体的牙体预备，表述错误的是（）
A.去除龋坏组织
B.提供良好的固位形和抗力形
C.洞缘预备短斜面
D.洞壁无倒凹
E.洞深不能少于6mm
---- Do you know Tom, ______ father is an engineer?
---- Yes, quite well. He ______ be the first to offer me help when I met with problems.
A．the; would
B．which; used to
C．that; used to
D．whose; used to
邻面龋坏，检查：见邻面接触点破坏，拟行邻
嵌体修复