—What do you plan to do on the ___________ May Day holiday?

—I have no idea. Probably, I will spend it by doing many papers.

A．three-day

B．three-days

C．three days

D．three day’s

下列哪种不是PFM的适应症（）。

A.氟斑牙

B.牙体缺损大无法充填者

C.前牙错位扭转不能正畸治疗者

D.青少年恒前牙的四环素染色牙

E.需要做烤瓷桥固位体的基牙