补全对话

从方框中选择最佳选项完成对话，有两项多余

a. Yes!

b. The keys? They're on the table.

c. No, they aren't.

d. How about my books?

e. It's under the desk.

f. Where are they?

g. Thank you very much.

A: Hi, Susan! My keys（钥匙） are lost（丢失）. ____

B: Are they on the table?

A:____

B: En. . . Are they in your bag?

A: But where is my bag?

B:____

A:____They are here. But there aren't any books in my bag.

B: Ha- ha. Are they lost, too?

A: Oh, no.

B: Look! They are on the shelf (架子).

A:____

B: Not at all.

 在中国科技馆“探索与发现A厅”，有一个有趣的磁悬浮灯泡，其示意图如图所示．在磁悬浮灯泡的内部装有一块永磁体，在灯泡上方的展柜中安装有永磁体和一个励磁线圈，给励磁线圈通电，在控制电路的调节下，永磁体和励磁线圈所产生的磁场能使灯泡静止悬浮在空中．关于灯泡受力情况，下列说法中正确的是（　　）