（2011·重庆师大附中月考）While he was investigating ways to improve the telescope, Newton made ________ discovery which completely changed ________ man’s understanding of color.
A. a; 不填 B. a; the C. 不填; the D. the; a
（2011·重庆师大附中月考）While he was investigating ways to improve the telescope, Newton made ________ discovery which completely changed ________ man’s understanding of color.
A. a; 不填 B. a; the C. 不填; the D. the; a
A考查冠词的用法。第一空表示“一个发现”；第二空understanding of color已有限定词man’s，故不用冠词。