He to play the piano before he was 11 years old.
- A.had learned
- B.has learned
- C.learned
- D.learns
答案
正确答案:A
知识点:动词时态:过去完成时

根据语境,由“before he was 11 years old”可知,是在过去这个时间点,他已经学会了弹钢琴。因此用过去完成时,即had learned。

略
