プログレッシブ和英中辞典(第4版)の解説
やく【役】
❶〔任務，役割〕duty; function
彼らはめいめいの役を立派にこなした
Each of them 「discharged his duty [did his own part] well.
彼は何も役がない
He has no particular 「duty to perform [function].
私は献立を決める役を引き受けた
I took on the job of planning the menu.
私には役が重過ぎる
The task is too much for me.／I am not equal to the task.
彼女は団長秘書の役で親善使節団に参加した
She joined the goodwill mission as [in the capacity of] the leader's secretary.
いざという時には傘でも武器の役を果たす
Even an umbrella will serve as a weapon in time of need.
❷〔地位〕a post；〔責任ある地位・公職〕an office
役を退く
retire from office
ただ１回の失策で彼はお役御免となった
He was dismissed from his post for just one mistake.
彼は次官の役に任ぜられた
He was appointed (to the office of) vice minister.
彼が市長の役にある間は汚職事件がなかった
While he was (in office as) mayor, there were no bribery scandals.
彼女の役は何ですか
What office does she hold?／What is her position [title]?
❸〔芝居の〕a role; a part
シーザーの役を演じる
play [act] the part [role] of Caesar
母と娘の二役を務める
perform the double role of mother and daughter
彼女にカルメンの役が振り当てられた
She was cast as [in the role of] Carmen.
❹〔トランプなどの〕
役が付く
gain extra [bonus] points for a special combination of cards [tiles]（▼tilesはマージャンで）
役に立つ
be useful; be of use
役に立たない
(be) useless／《口》 be not worth a hill of beans
あの青年はなかなか役に立つ
That young man is helpful in many ways.
私で何かお役に立ちましょうか
Can I be of any help to you?
そのような訓練もいつかは役に立つでしょう
Such training will help you someday.
この古い自転車が何かの役に立つだろうか
Can you find any use for this old bicycle?
泣いたところで何の役に立つのか
What's the use of crying?
えき【役】
❶〔人民に課する労働〕service；labor，《英》 labour
❷〔戦争，戦役〕a war; a battle
西南の役
the Battle of Seinan