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painstaking; careful; meticulous; scrupulous; detailed; elaborate
職人が丹念に木を削った。
The craftsman carefully shaved the wood.
丹念な手入れのおかげで庭が美しい。
Thanks to meticulous care, the garden is beautiful.
資料を丹念に調べ上げる必要がある。
Go through the materials thoroughly.