YOU SAID:

My brother is very unfriendly, and I do not know why he is so mean.

INTO JAPANESE

私の弟は非常にフレンドリーで、意地悪なんかわからないです。

BACK INTO ENGLISH

My brother is very friendly, I mean do not know.

INTO JAPANESE

私の兄は非常に友好的、私は意味がわからない。

BACK INTO ENGLISH

My brother is very friendly, I do not know the meaning.

INTO JAPANESE

私の兄は非常に友好的、私は意味がわからない。

BACK INTO ENGLISH

My brother is very friendly, I do not know the meaning.