--What is an e-pal ?

---An e-pal is someone you write e-mail to.

---__________.

A．Yes, all right.

B．OK. That’s all right.

C．Yes, you guessed it.

D．OK. You get it.

丝圈式缺隙保持器（）

A．丝圈应离开牙槽嵴0.5～lmm

B．丝圈应离开牙槽嵴2～3mm

C．丝圈应离开牙槽嵴0.5mm

D．与牙槽嵴贴近

E．丝圈应离开牙槽嵴1～2mm