Kokoro, by Natsume Soseki (paragraph #460)

「丈夫ですとも。何にも持病はありません」

translation

"I'm strong. I don't have any chronic diseases."

kanji (pronunciations & definitions)
丈夫: healthy (じょうぶ), robust, strong, solid, durable : what (なに), what (ナニ), you-know-what, you-know-what, that thing 持病: chronic disease (じびょう), bad habit, intractable habit

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