句子中的has been ,have been,had been 代表什么？

Question

完成时，和过去完成时吗？可以翻译成什么？
“jeff is a boy,for the past three years,has been a good fried of mine."是什么意思？

Answer 1

has been ,have been,现在完成时，已经去过
，已经成为，已经持续，

eg: she has been to Shanghai.他去过上海

I have been there before我以前去过那

She has been a teacher他已经成为一个老师

the film has been on for an hour，电影已经持续一个小时了

had been过去完成时,过去的过去

the film had been on for an hour before we got there

Answer 2

准确说是完成时和过去完成时的被动态。
可以翻译成“已经（被）....”

Answer 3

现在完成时，表示从过去某时开始一直延续到现在的动作和状态，通常用延续性动词。。。。
过去完成时，在时间上表示过去的过去。
意思都是已经。。。的意思。