āi
hey!
(interjection used to attract attention or to express surprise or disapprobation)
This is an interjection or onomatopoeia — it represents a sound.
哎哟
āi yō
hey
哎呀
āi yā
interjection of wonder, shock or admiration
哎呦
āi yōu
(interjection of surprise, pain, annoyance etc)
哎唷
interjection of pain or surprise