obliged to,例如:
1、I felt obliged to ask them to dinner.我不得不請他們吃飯。
2、The storm got worse and worse. Finally, I was obliged to abandon the car and continue on foot.暴風雨愈發猛烈,我最終不得不棄車步行。
3、I'm much obliged to you for helping us.承蒙相助,本人不勝感激。