I'm am a bit confused here. I don't really get what tense I should use after 'has been a long time'.
Are these correct? If not, why? What do they mean?
1. It has been a long time since I called you out.
2. It has been a long time since I have called you out.
3. It has been a long time since I had called you out before that dinner we had..
4. It has been a long time since I had called you out.
Thanks.