YOU SAID:

We were unavoidably delayed.

INTO JAPANESE

やむを得ず遅れました。

BACK INTO ENGLISH

I was unavoidably late.

INTO JAPANESE

やむを得ず遅かった。

BACK INTO ENGLISH

It was unavoidable that it was late.

INTO JAPANESE

遅れることは避けられませんでした。

BACK INTO ENGLISH

It was inevitable to be late.

INTO JAPANESE

遅れることは避けられませんでした。

BACK INTO ENGLISH

It was inevitable to be late.