(in) duty bound意为“有责任(做某事)；感到应该”；(in) honor bound指“道义感使不得不；在道义上应该”，两者均后接不定式。

• We're in duty bound to help the needy or those in distress.
  我们应该帮助那些穷苦人或不幸的人们。
• In duty bound , he went back to see his parents.
  受责任驱使，他回去看了父母。
• You're (in) honor bound to give him help when he did the same for you.
  他帮过你，你在道义上也应该给他帮助。
• I felt honor bound to help him when he was in difficulty.
  在他处于困难中时，我觉得在道义上应该帮助他。