YOU SAID:

I have found that I simply do not have the capacity to understand how you can be so stupid.

INTO JAPANESE

私には、あなたがどうしてそんなに愚かであるかを理解する能力がないことがわかりました。

BACK INTO ENGLISH

I found that I didn't have the ability to understand why you were so stupid.

INTO JAPANESE

私にはあなたがなぜそんなに愚かだったのか理解する能力がなかったことがわかりました。

BACK INTO ENGLISH

It turns out that I didn't have the ability to understand why you were so stupid.

INTO JAPANESE

なぜあなたがそんなにバカだったのか理解する能力がなかったことがわかりました。

BACK INTO ENGLISH

It turns out that I didn't have the ability to understand why you were so stupid.