it was a mistake
It was a huge mistake.
It was a mistake.
Tom dice che era un errore.
Tom says it was a mistake.
I told him it was a mistake.
Sa che ciò che ha fatto era un errore.
He knows what he did was a mistake.
Obviously it was a mistake.
Dica a Tom che era un errore.
Tell Tom it was a mistake.
I told her it was a mistake.
It was an honest mistake.
Tell him it was a mistake.