I have studied English for five years I was ten years old.A. afterB. sinceC. beforeD. whe

问题补充：

I have studied English for five years I was ten years old.

A. after

B. since

C. before

D. when

答案：

A. after

(答案→)B. since

C. before

D. when

解析：四个选项分别表示在……之后（将来时态）、从……开始（一般现在时态）、在……以前（主句为过去完成时态）和当……时（主从时态一致），句子为现在完成时态，故选B，从我十岁开始。