What concepts are described in the following sentence?

"Olympiacos F.C. were past champions in the Greece Superleague in which AEK Athens FC also compete. AEK Athens home ground is in Athens and they have 69618 members."

Return the answer as pairs of triples.
AEK Athens F.C. LEAGUE Superleague Greece
Superleague Greece CHAMPIONS Olympiacos F.C.
AEK Athens F.C. GROUND Athens
AEK Athens F.C. NUMBER_OF_MEMBERS 69618