基本信息
二、单项选择 （15%）
21. It is reported that ________ European chemist called Felix Hoffmann first produced ASA which completely changed ________ man’s understanding of aspirin.
A. a; /B. an; aC. the; aD. an; /
22. His point puzzled us so much that no one could ________.
A. turn it outB. make it outC. try it outD. let it out
