To tell you truth he is not John I know before.A. the; theB. a; aC. a ; the D. /; a

问题补充：

To tell you truth, he is not John I know before.

A. the; the

B. a; a

C. a ; the

D. /; a

答案：

(答案→)A. the; the

B. a; a

C. a ; the

D. /; a

解析：考查定冠词的特殊用法。to tell you the truth是固定表达方式，“跟你说真的；说实话”，John作为专有名词一般不与冠词连用，但本题中John后面有修饰语“我以前所认识的”，因此是特指，需要加定冠词。