21. First of all, I hope that we shall never lose _____ heart in face of _____ failure.
A. the; a B. the; the C. 不填; 不填 D. a; 不填
22. I knew we would be friends ____ I met you on campus.
A. the first time B. at the first time C. for the first time D. by the first time
23. Is it the years ______ you worked in Africa as a doctor ______ have a great effect on your literary works？
A. that; where B. that; that C. when; where D. when; that
