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keenly; deeply; fully; heartily; seriously; earnestly
calmly; quietly; softly
fixedly (gazing, staring); intently
秋の夜にしみじみ考えた。
I thought deeply on an autumn night.
彼女はしみじみと涙を流して話し始めた。
She began to speak while quietly shedding tears.
昔のことをしみじみと思い出している。
I'm deeply reminiscing about the old days.