国之交在于民相亲 The key to sound relations between states lies in amity between the people ; Friendship between peoples holds the key to building sound state-to-state relations.

世纪之交 the turn of the century ; turn of the century

国之交在于民相近 amity between people holds the key to the sound relations between countries

莫逆之交 sworn friend ; damon and pythias

泛泛之交 nodding acquaintance

点头之交 a nodding acquaintance ; casual acquaintance

饭饭之交 No Strings Attached

心灵之交 Meeting Soul-mates

患难之交 A Friend in need ; friends in adversity

生死之交 Damon and Pythias ; A friend until death ; Amici per la pelle