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(teacher's) platform; podium; dais
新任教師が教壇に立つ。
The new teacher steps onto the podium.
彼は教壇で四十年間教え続けた。
He continued teaching from the podium for forty years.
先生が教壇に上がるまで生徒たちはざわついていた。
The students were chattering until the teacher stepped up to the podium.