勢いきおいよく

adverb

vigorously; with great force; energetically

Describes doing something with momentum, force, or lively energy. Often used for physical actions, but can also apply to enthusiastic or spirited behavior.

• 彼かれは勢いきおいよくドアを開あけた。

  He opened the door with great force.

• 子こどもたちは勢いきおいよく校こう庭ていに飛とび出だした。

  The children energetically rushed out into the schoolyard.