In 1778 Banks was elected president of the Royal Society position he held for 42 years.A

问题补充：

In 1778, Banks was elected president of the Royal Society, position he held for 42 years.

A. /, a

B. / , the

C. the, a

D. the, the

答案：

(答案→)A. /, a

B. / , the

C. the, a

D. the, the

解析：句意：在1778年，班克斯被选举为英国皇家科学院的主席，这个职位他担任了42年了。第一空中表示职位的前面不加the,第二空中泛指一个职位，故用a，来修饰，故选A