观察下列句子，指出黑体部分所属的时态。
1．By the time he was 14，Mozart had composed many pieces for the harpsichord，piano and violin，as well as for orchestras.
一般过去时；过去完成时
2．After they had known each other for many years，Beethoven said，“He is a good composer，but he has taught me nothing.”
过去完成时；一般过去时
3．Before they visited India，they had recorded seven albums.
一般过去时；过去完成时
