come的过去式和过去分词是什么意思

　　例句

　　1、Two police officers came into the hall.

　　两位警官走进大厅。

　　2、Eleanor had come to visit her.

　　埃莉诺来看过她了。

　　3、He came to a door that led into a passageway.

　　他来到一扇门前，这扇门通往一条走廊。

　　4、Thewatercameuptomychest.

　　水淹到了我的胸部。