gain [gather, build (up)] momentum
勢いがつく,勢いを増す
gain [loss] of prestige
威信の獲得[失墜]
gain on foreign exchange
外国為替差益
gain [lack] one's confidence
自信を得る[欠く]
gain [win, achieve] one's end(s)
目的を達成する
gain [get] one's experience in writing
書く経験を積む
gain [apply, demonstrate] practical knowledge of ...
…の実際的な知識を得る[用いる,示す]
gain [win] promotion
昇進する
gain [acquire, obtain] qualifications for ...
…の資格を取る
gain seats
議席を獲得する