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lecture (esp. special engagement by noted speaker); lecture meeting (event with one or more lectures)
有名な学者の講演会に参加した。
I attended a lecture by a famous scholar.
地元で大きな講演会が開かれた。
A large lecture event was held in the area.
地域の講演会でボランティア活動について話した。
I spoke about volunteer activities at a community lecture.