〔熱意のない〕unenthusiastic ((about));〔気乗りのしない〕half-hearted;〔無関心な〕indifferent ((about, to))

    • 彼らはその企てに不熱心であった
    • They 「were not enthusiastic about [showed little enthusiasm for/were indifferent to] the enterprise.
    • 勉強に不熱心なので落第した
    • He studied so half-heartedly that he failed in his examinations.
    • 家事に不熱心である
    • She takes no interest in housework.