1)某些动词的主动形式表示被动意义。这些动词有：cook, read, shut, smell, taste, was, prove等。
【例如】
The dishes smell and taste delicious. The play reads better than it acts. The theory proved right at last.
2)“be＋过去分词”并不都
是被动语态，也可能是系表结构,表示主动意义。
【例如】
The street was covered with snow. On Christmas day, the church was crowded with people.
