It is years since I enjoy myself so much

It is years since I enjoy myself so much it is years since i enjoyed myself so much It was years since I ___________ (enjoy) myself so much.填什么, It's years (since) I enjoyed myself so much.Why? It's years since l enjoy myself so much.since可否换成before? It has been many years since I enjoyed myself so much. it's years since i enjoyed myself so much.中文意思是否为：我已经好多年没这么开 It is been years _________ I enjoyed myself so much as last it 's years ______ i enjoyed myself so much It's years when I enjoyed myself so much.翻译,并解释这里when的用法 It is 5 years since he __ ,so his health is much better now. It is 5 years since I have lived here.It is 5 years since I