obliged to，例如：

1、I felt obliged to ask them to dinner.我不得不请他们吃饭。

2、The storm got worse and worse. Finally， I was obliged to abandon the car and continue on foot.暴风雨愈发猛烈，我最终不得不弃车步行。

3、I'm much obliged to you for helping us.承蒙相助，本人不胜感激。