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curtain raising; starting (e.g. play, concert)
開演の十分前に客席に着いた。
I took my seat ten minutes before the curtain rose.
雨天のため開演時間が遅れた。
The start time was delayed due to rain.
開演を告げるベルが鳴り響いた。
The bell announcing the start of the show rang out.