YOU SAID:

A quick brown fox maybe didn't jump over the lazy dog.

INTO JAPANESE

素早い茶色のキツネは怠け者の犬を飛び越えられなかったかもしれない。

BACK INTO ENGLISH

The quick brown fox could not have jumped over the lazy dog.

INTO JAPANESE

素早い茶色のキツネは怠け者の犬を飛び越えることはできなかったでしょう。

BACK INTO ENGLISH

The quick brown fox could not have jumped over the lazy dog.