-지(요)
I guess you could say that sometimes it implies that the speaker is either asking for agreement, insisting on something, or saying something that both parties are aware of.
Stephen이지? You're Stephen, right? or You're Stephen, aren't you?
내가 좀 늦었지? I'm a little late, aren't I?
미국에 처음 오신 게 아니지요 (죠)? This isn't your first time in the States, is it?
춥지? You're cold, aren't you? or It's cold, isn't it?
당연하지. Of course.
올거지? You'll come, right?
가야지. Of course, I have to go.
와야지. You have to come.
힘들겠지. It must be hard.
-네(요) can express surprise, when the speaker is taking in information that wasn't known before. Or it can simply mean that the speaker is making a remark and doesn't expect a response.
생각보다 맛있네(요). It tastes better than I thought it would.
재미있네.
돈이 없네.
And here's the sarcastic one that my friends like to use... 역시 똑똑하네.
된/되/될
Do you have an example of where you saw this? It's a matter of tense.
잘 된거야 past
잘 되는거야 present
잘 될거야 future
Hope this helps a little. I'm sure the other folks will be able to add a lot more or correct me where I'm wrong or missing something. Good luck!
