John Cena does not have a tag team partner because he is a singles wrestler. Cena has never been a tag team wrestler in his career. though he has won the WWE Tag Titles multiple times with partners like Shawn Micheals, Miz etc, he has never been a tag team guy. He has been a singles wrestler and has had a lot of success individually.
It is batista and Shawn michaels
The Undertaker's tag-team partner is Kane
the Great Khali doesn't have a tag team partner because he doesn't compete in tag team matches.
the great khalis tag team partner is r-truth.
EDGE
sin cara or Rey Mysterio
vikki
jim neidhart
kelly kelly
Just beat someone and they'll ask to be your tag partner.
press square
cm punk they had the world tag team titles