YOU SAID:

I went in your school by the way, and one day i killed your bestfriend

INTO JAPANESE

ところで私はあなたの学校に行きました、そしてある日私はあなたの親友を殺しました

BACK INTO ENGLISH

By the way I went to your school and one day I killed your best friend

INTO JAPANESE

ところで、私はあなたの学校に行き、ある日私はあなたの親友を殺した

BACK INTO ENGLISH

By the way, I went to your school and one day I killed your best friend

INTO JAPANESE

ところで、私はあなたの学校に行き、ある日私はあなたの親友を殺しました

BACK INTO ENGLISH

By the way, I went to your school and one day I killed your best friend