21. He has ___good knowledge of science and ____sense of humour..
A. a , / B .a, a C. / , a D. /, /
22. Although it is not our normal _______to give credit in our shop, this time I think we should consider the matter more closely.
A. habit B. practice C. action D. intension
23. I would appreciate _______, to be frank, if goods could be delivered as soon as possible.
A. you B. this C. it D. myself
