YOU SAID:

Un homme averti en vaut deux

INTO JAPANESE

事前に警告されたことは事前に警告されました

BACK INTO ENGLISH

What has been forewarned has been forewarned

INTO JAPANESE

事前に警告されたものは事前に警告された

BACK INTO ENGLISH

The forewarned were forewarned

INTO JAPANESE

警告を受けた者は警告を受けた

BACK INTO ENGLISH

Those who were warned were warned.

INTO JAPANESE

警告された者は警告された。

BACK INTO ENGLISH

Those who were warned were warned.