YOU SAID:
i ate a dolphin in my grandpa
INTO JAPANESE
おじいちゃんでイルカを食べました
BACK INTO ENGLISH
I ate a dolphin with my grandpa
INTO JAPANESE
おじいちゃんと一緒にイルカを食べました
BACK INTO ENGLISH
I ate a dolphin with my grandpa
That didn't even make that much sense in English.