YOU SAID:

I had one mistake, but I don't know why. And he had the last one wrong.

INTO JAPANESE

私は1つ間違いをしましたが、私はその理由を知りません。そして彼は最後のものを間違っていました。

BACK INTO ENGLISH

I made one mistake but I do not know the reason. And he was wrong with the last one.

INTO JAPANESE

私は1つミスをしましたが、理由はわかりません。そして彼は最後のものと間違っていました。

BACK INTO ENGLISH

I made one mistake but I do not know the reason. And he was wrong with the last one.