责无旁贷

zhè kěn dìng shì zé wú páng dài de

这肯定是责无旁贷的。

It is certainly an inescapable duty.

wǒ jué de bāng zhù tā shì zé wú páng dài

我觉得帮助他是责无旁贷。

I felt duty-bound to help him.