Dr. Peter Spence, headmaster of the school, told us, “fifth of pupils here go on to study

Dr. Peter Spence, headmaster of the school, told us, “ fifth of pupils here go on to study at Oxford and Cambridge.”
A. /；A
B. /；The
C. the; The
D. a; A

(答案→)A. /；AB. /；TheC. the; TheD. a; A解析：句意：彼得·斯宾塞博士是这个学校的校长，他告诉我们“这里1/5的学生继续去牛津和剑桥大学学习”。 headmaster of the school是同位语，同位语的表示职位的前面不用冠词；这里1/5的表达方式可以是a fifth或one fifth,故选A。

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