How to say you have already eaten the cake. in Japanese
1)
ケーキケーキ(keki) (n) cakeをを(wo) (prt) indicates direct object of action/indicates subject of causative expression/indicates an area traversed/indicates time over which action takes place/indicates point of departure or separation of action/indicates object of desire, like, hate,もうもう(mou) (adv,int) already/anymore/soon/shortly/more/further/other/again/interjection used to strengthen expression of an emotion食べてno dictionary result, likely a conjigated verbno dictionary result, likely a conjigated verbしまったしまった(shimatta) (int) damn it!/damn!/oops!/oh dear!/oh no!。。(。) Japanese period "."
