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at once; immediately; without delay; promptly
雑誌で見つけた新しいレシピを早速試してみた。
I immediately tried out the new recipe.
彼は早速行動を起こして問題を解決した。
He immediately took action and solved the problem.
買ったばかりの本を早速読み始めた。
I immediately started reading the book I had just bought.