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keenly; deeply; fully; heartily; seriously; earnestly
calmly; quietly; softly
fixedly (gazing, staring); intently
故郷の写真を見てしみじみ懐かしんだ。
I looked at photos of my hometown and felt nostalgic.
彼の話を聞いてしみじみ感動した。
I was deeply moved listening to his story.
老後のことをしみじみ考えるようになった。
I've started to deeply think about old age.