探究发现
①He asked me where I had been during the summer holidays.
②What had Jane done by the time she was seven?
③I had learned 900 English words by the time I was ten.
④She had lived here for a few years before she moved to Beijing.
⑤By the time my parents reached home yesterday, I had cooked the dinner already.
⑥Had you ever seen her before that?
[我的发现]
1．过去完成时由“had＋过去分词”构成。
2．过去完成时的疑问句，将had提前。
