从A．B．C．D．四个选项中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。
21.----- What are you talking about?
----- _______.It’s a private conversation.
A．None of your business! B．Forget it!
C．Who cares ? D. Don’t mention it.
22. In the United States, there is always ____ flow of people to areas of ____ country where more jobs can be found.
A. a; the B. the; a C. the; the D. a; a
23．At first I was worried about it, but the party _______ to be a success.
A．turned up B．turned down C. turned in D. turned out
