hey /hei/, hi /hai/ interj. ! (打招呼)!(促使注意,表示惊异,询问,相当于hihello): Hey! where are you going?嘿,到那儿去? Hey, Alice! This is Fred. 喂,阿丽丝,这是弗雷德。 

hi /hai/ interj(用作问候语)嘿,喂(cf.hey