21. ____ he does has nothing to do with me.
A. Whatever B. No matter what C. That D. If
22. The manager came over and asked the customer how____
A. did the quarrel came about B .the quarrel had come about
C. had the quarrel come about D. had the quarrel come about
23. Energy is ____makes thing work.
A. what B. something C. anything D. that
