John university professor is considered to be success as expert in the agriculture r

问题补充：

John, university professor, is considered to be success as expert in the agriculture research.

A. a; a; an

B. an; / ; an

C. the; /; an

D. a; the; an

答案：

(答案→)A. a; a; an

B. an; / ; an

C. the; /; an

D. a; the; an

解析：考察冠词。第一空泛指一位大学教授，university的第一个音素是辅音，所以用a;第二孔的success是抽象名词具体化了，指成功的人或者成功的事物，这里指一个成功的人。第三空的泛指一位expert，以元音开始，所以使用an.