am/is/are的过去式和过去分词

　　We had to work within the parameters that had already been established.

　　我们必须在已设定的范围内工作。

　　No new SARS cases have been reported in the region.

　　该区没有新增非典型肺炎病例。

　　Inflation was so high that the notes were like Monopoly money.

　　通货膨胀严重，货币变得跟“大富翁”游戏钞票无异。

　　She was still half asleep when she arrived at work.

　　她到了上班地点时仍然睡眼惺忪。