Carefully; with great care — an adverb meaning to treat something or someone with attention, tenderness, or caution.
このアンティークの皿は大切に箱に入れて保管している。
I keep this antique plate carefully packed in a box.
子どもを大切に育てることが大事だと思う。
I think it's important to raise children with care.
ケーキは冷蔵庫で大切に保存してください。
Please store the cake carefully in the refrigerator.