driving force
US /ˈdraɪvɪŋ fɔrs/
UK /ˈdraɪvɪŋ fɔrs/

名詞
1.
原動力, 推進力
something that provides the power to make something happen
例:
•
Innovation is the driving force behind the company's success.
イノベーションは会社の成功の原動力です。
•
His passion for justice was the driving force in his career.
彼の正義への情熱がキャリアの原動力でした。
Lingolandでこの単語を学ぶ