- 悔不当初 huǐbùdāngchū to regret one's past deedsTo regret bitterly what one did (or did not do) in the first place.
- 罚不当罪 fábùdāngzuì punishment not fitting the crimeThe punishment is disproportionate to the crime committed, usually referring to being punished too severely; literally, "the punishment does not equal the crime"
- 万夫不当 wànfūbùdāng unbeatableextremely brave and strong; literally describing someone so powerful that even ten thousand men could not stop them
- 不当回事 bùdànghuíshì to not take seriouslyto not care about something; to treat something as unimportant or not worth considering
- 不当家不知柴米贵 bùdāngjiābùzhīcháimǐguì you don't know the cost of living until you run a householda person who does not manage a household would not be aware of how expensive it is to live; often used to remind someone to be less wasteful or more appreciative of resources
- 不当得利 bùdàngdélì unjust enrichmentunjust enrichment; profits or benefits acquired illegally or unfairly at the expense of others
- 不当紧 bùdāngjǐn unimportantof no consequence; not serious; it doesn't matter
- 名不当实 míngbùdāngshí to not live up to one's reputationto have a name or reputation that does not match the actual reality; to be merely a nominal title or empty fame
- 并无不当 bìngwúbùdàng nothing improperthere is nothing wrong or improper about it; entirely appropriate
- 用词不当 yòngcíbùdàng inappropriate wordingincorrect or unsuitable choice of words; imprecise or improper expression
- 说话不当话 shuōhuàbùdànghuà to break a promiseto fail to keep to one's word; to go back on what one said
- 不当一回事 bùdàngyīhuíshì to not take seriouslyTo not regard something as a matter of any importance; to treat something as if it does not matter.
- 不当事 bùdāngshì uselessto be of no use or consequence
- 不当作一回事 bùdàngzuòyīhuíshì to not take seriouslyto not take as a serious matter; to pay no attention to; to treat with indifference or as being of no importance