—Really ? Who will give lecture ? What is it about ?—Professor Chen , president of Beijin

．—Really ? Who will give lecture ? What is it about ?
—Professor Chen , president of Beijing University . About pollution .
A. the ;a
B. the;/
C. a ; the
D. a ;/

A. the ;a B. the;/ C. a ; the (答案→)D. a ;/解析：president 作同位语，前不加冠词。

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