YOU SAID:

I violently threw up on you cousins sister

INTO JAPANESE

私は激しくあなたのいとこの妹に投げつけた

BACK INTO ENGLISH

I violently threw it at your cousin's sister.

INTO JAPANESE

私は激にあなたのいとこの妹にそれを投げました。

BACK INTO ENGLISH

I violently threw it at your cousin's sister.