YOU SAID:

I just ate a cow the size of a cow

INTO JAPANESE

私は牛を牛の大きさだけ食べた

BACK INTO ENGLISH

I ate the cow as much as the size of the cow

INTO JAPANESE

私は牛の大きさと同じくらい牛を食べました

BACK INTO ENGLISH

I ate cows as much as the size of the cow

INTO JAPANESE

私は牛の大きさと同じくらい牛を食べました

BACK INTO ENGLISH

I ate cows as much as the size of the cow