问题

I wonder how much you charge for your service–The first two are free____ the third costs $30

A:before
B:as
C:when
D:while

正确答案是：

同类题型

Being a teacher________ hard.

He is the English teacher___________ help we have made great progress.

It is believed thatintelligence is to _____ extent _____ we are born with

Please wait a moment. I have ____ to tell you.—OK!

I think Helen studies English as ________ as Lucy.—I don’t think so. Helen often makes mistakes.