think的過去式和過去分詞是什么

　　例句：

　　1、I certainly think there should be a ban on tobacco advertising.

　　我確實認為應該禁止香煙廣告。

　　2、Nora thought he was seventeen years old.

　　諾拉覺得他有17歲。

　　3、You were probably brought up to think like that.

　　你可能從小就被教育那樣考慮問題。