YOU SAID:
He ain't heavy, he's my brother.
INTO JAPANESE
彼は重くないです、彼は私の兄弟です。
BACK INTO ENGLISH
He is not heavy, he is my brother.
INTO JAPANESE
彼は重くないです、彼は私の兄弟です。
BACK INTO ENGLISH
He is not heavy, he is my brother.
That didn't even make that much sense in English.