YOU SAID:

This never would've happened at 100.

INTO JAPANESE

これは 100 では決して起こらなかったでしょう。

BACK INTO ENGLISH

This would never have happened in 100.

INTO JAPANESE

これは100年には決して起こらなかったでしょう。

BACK INTO ENGLISH

This would never have happened in 100 years.

INTO JAPANESE

これは100年で決して起こらなかったでしょう。

BACK INTO ENGLISH

This would never have happened in 100 years.