YOU SAID:

I can't believe you're unable to understand why I chose this

INTO JAPANESE

私がこれを選んだ理由を理解できないとは信じられません

BACK INTO ENGLISH

I can't believe I can't understand why I chose this

INTO JAPANESE

なぜこれを選んだのか理解できないと信じられない

BACK INTO ENGLISH

I can't believe I don't understand why I chose this

INTO JAPANESE

なぜこれを選んだのかわからない

BACK INTO ENGLISH

I don't know why I chose this

INTO JAPANESE

なぜこれを選んだのか分かりません

BACK INTO ENGLISH

I don't know why I chose this