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slim; slender; lithe; supple
smoothly; without resistance; without trouble; without difficulty; without dissent; easily; readily
交渉はすんなりまとまった。
The negotiations were settled smoothly.
彼の提案はすんなりと受け入れられた。
His proposal was smoothly accepted.
事態はすんなり解決するとは思っていなかった。
I didn't expect the situation to be resolved so smoothly.