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continuously; from beginning to end; from first to last
明るい性格の彼は始終笑顔を絶やさなかった。
He kept smiling the whole time.
彼は始終穏やかな表情を崩さず話し続けた。
He kept talking with a calm expression from beginning to end.
重要な会議中だったので始終メモを取っていた。
I was taking notes throughout the meeting.