潜泳的人，从水下向上看，会看到一彩色镶边、内有图象的圆面，那么（　　）

A．圆面内只能呈现水面上的部分景物

B．彩色镶边是由于水面四周各种物体的颜色所引起的

C．彩色镶边是由于不同颜色的光折射程度略有不同所致

D．圆面中图象呈现的是水面外的景物，且看到景物的高度比实际景物要低

根据对话内容，填入恰当的句子，补全对话。

A: What a fine day today!      1       ?

B: That sounds like a good idea.       2      ?

A: Let's go to the little Hill.

B: Shall we take the bus there?

A:        3     ．It's not very far.

B: That will be OK. I'll ride my new bike my father bought me for my birthday last month.

A:      4      ?

B: Let's ask Mary and Jack to go with us. They planned to go last Sunday but it rained.

A: Good! I'm sure they will be happy.

B: Have you got any idea what we are doing there?

A:       5     .

B: That will be fun.