prove to be

prove to be something

to be shown to be someone or something; to be found to be someone or something. Susan proved to be a good friend when she lent me some money. The food proved to be spoiled when I smelled it.
See also: prove
References in classic literature ?
He assured Emily that he had only decided on writing to her, after some hesitation, in the hope of serving interests which he did not himself understand, but which might prove to be interests worthy of consideration, nevertheless.