have/has+过去分词与jave/has been+过去分词有什么区别

问题描述:

have/has+过去分词与jave/has been+过去分词有什么区别

前面一个是现在完成时的时态构成,eg.I have learnt English for three years.
后面一个是现在完成时的被动结构 eg.English has been learnt by a lot of people.