YOU SAID:

why is my horse eating all of my great grandmothers apples from last year

INTO JAPANESE

去年から私の馬は私の祖母のりんごを全部食べている

BACK INTO ENGLISH

Since last year my horse has eaten all my grandmother's apples

INTO JAPANESE

昨年から私の馬は私の祖母のりんごを全部食べてきました

BACK INTO ENGLISH

Since last year my horse has eaten all my grandmother's apples