► 名詞
難題 [なんだい] meaning: demand rank: 4
☆ 難題を吹っかける ⇨
難題 [なんだい] meaning: problem rank: 4
☆ 人類は人口の爆発的増加と環境保全の両立という難題を抱えている ⇨ Humans face an extremely difficult problem of dealing with the explosive population increase and the environment protection at the same time (☛ Literally “difficult issue”)
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