材料2：二战期间，德国占领巴黎，德军将领参观巴黎的毕加索艺术馆。毕加索发给每人一幅《格尔尼卡》的复制品。一位德国军官问他：这是您的作品吗？毕加索面色严峻地说：不，这是你们的作品。

用方框中所给动词的适当形式完成下列句子。

I ____my teeth three times yesterday.
When I was a child, I ____ to be a doctor.
We ____ our vacation last year. We stayed at a very nice hotel.
Amy's grandfather____ when he was 90 years old.
The concert ____ at 7:30 and ended at 10:00.