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becoming a pupil (of); becoming a disciple; entering an institution; beginning training
introduction (to); primer; guide
entering through a gate
彼は剣道道場に入門した。
He entered the kendo dojo.
彼は著名な師匠に弟子として入門を許された。
He was permitted to become a disciple of the renowned master.
彼女は伝統ある陶芸工房に弟子入りするため入門を決意した。
She decided to enter the long-established pottery studio to become an apprentice.