第一志望の大学に落ちて、彼はひどく落胆した。
He was deeply disappointed when he failed to get into his first-choice university.
試合に負けても、選手たちは落胆の色を見せなかった。
Even after losing the match, the players showed no sign of discouragement.
一度の失敗でそんなに落胆することはないよ。
There's no need to be so disheartened over a single failure.