什么时候后才用过去分词

过去分词在以下几种情况下使用：
（1）表被动：be done
（2）完成时（不论是过去完成时还是现在完成时）：have/has done
（3）虚拟语气

现在完成时，过去完成时，被动语态，过去分词作定语等用过去分词，如
He has finihed his homework.
The train had left when I got to the station.
Rice is grown in South China.
The boy called Jim is from America.

分鬼哭狼嚎