So far, about 40 houses have fallen down

--- The floor is dirty. Can anyone clean it?

---         . I do it all the time.

A．Don’t mention it.

B．Why you?

C．Not sure.

D．Not me again.

管道安装中，法兰的安装位置应根据螺孔位置确定平、立（）。

A.高低

B.位置

C.垂直

D.准确

—Sandra failed to pass the exam.

— __________ ? Nobody works harder than she does.

A．How come

B．How about

C．Why not

D．What for

依是否享有票据权利和享有的票据权利是否有瑕疵为标准，持票人分为______和______、______。

在HTML中可以使用______标记向网页中插入GIF动画文件。

A．＜FORM＞
B．＜BODY＞
C．＜MOVIE＞
D．＜IMG＞