May well
After the auxiliary verbs may, might or could, we sometimes add the adverb well to emphasise that something is possible or even likely.
E.g.
He may recover from the accident — Puede que se recupere del accidente
He may well recover from the accident — Es muy posible que se recupere del accidente
It could be a cause for concern — Podría ser motivo para preocuparse
It could well be a cause for concern —Bien podría ser motivo para preocuparse
