不得不

bùdébù
adverb HSK 3 #1,088

Meanings

  1. 1 have no choice but to
  2. 2 have to

Characters

Double negation: 'cannot not' = 'must/have to.'

Examples

Xià yǔ le, wǒ bùdébù dài sǎn.
It's raining, I have to bring an umbrella.
Tā bùdébù fàngqì le.
He had no choice but to give up.
Wèile zhuàn qián, tā bùdébù jiābān.
To earn money, he has to work overtime.

Tips

grammar
不得不 emphasizes reluctance — you HAVE to do it even though you'd rather not. Compare with 必须 which is neutral obligation.
memory
Think of it as 'can't NOT do' — a double negative making a strong positive.

Stroke Order