"I am waiting for you."
Translation:Jag väntar på dig.
It's "dig" because it's in accusative. I see you're doing German and Spanish; it's like "ich warte auf dich" rather than "ich warte auf du", or "yo te espero" rather than "yo tú espero".
As for "på", that's just the preposition Swedish uses when waiting for somebody.
Is there a general rule for when to us på like I noticed that på is used with ligger when talking about where things are
It's generally suitable whenever English uses on, or German uses auf. There are plenty of exceptions, but that should work as the most common case.
would "Jag invänter dig" mean essentially the same or not? what is the nuance difference between the two expressions?
That's inväntar, it basically means "await" rather than "wait (for)".
i understand that much. but as far as i can see (sorry, i'm not a native english speaker) "await smbd" and "wait for smbd" mean essentially the same, the nuances are rather stylistic than semantic. what about "väntar för" vs "inväntar"?
väntar på just means waiting in general, but inväntar means that you're waiting for something or somebody, and then something else happens.
For instance, you could both vänta på or invänta some test results, but if you use inväntar, it would imply that you're e.g. waiting for the results so you can make some decision.
If am right english often uses "i am waiting you" albeit i guess it is a slang term. Can swedish operate similarly
Yes and no - jag väntar dig is a fine phrase but it means "I'm expecting you".