Answers

2015-11-19T10:50:01+05:30
I think this would be more appropriate: 
a long time ago, i got graduated/
it has been a long time since i have graduated

0
2015-11-19T11:46:53+05:30
No...it's is not the right sentence....
0
There is no word gotten in english
get got and gotten
pt:got and ppt:gotten
No gotten word
Get got got