21. ---How long are you staying?
--- I don’t know. ____.
A. That’s OK. B. Never mind C. It depends D. It doesn’t matter.
22. His plan ended in _____, so as a writer, he was _____ complete failure.
A. the; / B. /; a C. /; the D. the; a
23.It’s necessary to be prepared for a job interview. ____ the answers ready will be of great help.
A. To have had B. Having had C. Have D. Having
