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illness (usu. excluding minor ailments, e.g. common cold); disease; sickness
bad habit; bad behaviour; weakness; failing
crazy; insane; disturbed; sick in the head
病気で学校を休んだ。
I was absent from school due to illness.
病気にならないように気をつけて。
Take care so you don't get sick.
長い病気のあとやっと元気になりました。
I finally recovered after a long illness.