Kokoro, by Natsume Soseki (paragraph #1136)

「其先生は何をしてゐるのかい」と父が聞いた。

translation

"What is the teacher doing?" my father asked.

kanji (pronunciations & definitions)
先生: teacher (せんせい), instructor, master, sensei, title or form of address for a teacher, master, doctor, lawyer, etc. : what (なに), what (ナニ), you-know-what, you-know-what, that thing : father (あて), father (かそ), father (かぞ), father (しし), father (ちち)

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