不三不四

1. Basic Information

• Pinyin: bù sān bù sì
• English Translation: Neither fish nor fowl (shady or dubious)
• Idiom Composition: 「不」（Not (negation)）＋「三」（Three (representing a standard or stable position in this context)）＋「不」（Not (negation)）＋「四」（Four (representing a standard or stable position in this context)）
• Meaning: Describes someone or something that is improper, shady, or of dubious character. It is a derogatory term used to criticize people with bad reputations or things that are odd and unclassifiable.

2. Detailed Meaning and Nuances

「不三不四」 contains the following nuances:

• Improper conduct (applied to people): This is the most common usage, referring to people who are untrustworthy, have bad reputations, or are morally questionable, such as thugs or delinquents.
• Dubious nature (applied to objects or styles): Refers to clothing or styles that are bizarre, do not fit into established categories, and appear unpleasant or ridiculous to others.

3. Usage

「不三不四」 is mainly used in the following contexts:

• Warning about social circles: Often used to advise children or friends against associating with people of poor character.
  • Example:「父母总是担心孩子在外面结交那些不三不四的朋友。」
    （Parents are always worried about their children making shady friends while they are out.）
• Criticizing improper relationships: Used to condemn extramarital affairs or relationships that are considered morally unacceptable.
  • Example:「他背着妻子在外面搞不三不四的关系，最终导致了离婚。」
    （He had an improper relationship behind his wife's back, which eventually led to a divorce.）
• Criticizing strange appearance: Used when someone's clothing or design is too eccentric, lacking class, or simply nonsensical.
  • Example:「这种不三不四的打扮，去参加正式面试肯定不合适。」
    （This indecent outfit is definitely not suitable for a formal interview.）

Additional Examples:

1. 别把那些不三不四的东西带回家。
   （Don't bring those shady things home.）
2. 那个街区治安不好，经常有一些不三不四的人在游荡。
   （The security in that neighborhood is poor, and there are often shady characters loitering around.）
3. 他整天不务正业，跟一群不三不四的人混在一起。
   （He neglects his duties all day and hangs out with a group of good-for-nothings.）
4. 这文章写得不三不四，逻辑完全不通。
   （This article is written in a messy and improper way; the logic doesn't make sense at all.）

4. Cultural Background and Notes

• There are several theories regarding the origin of the numbers 'three' and 'four.' One theory suggests that in the I Ching (易经), the third and fourth lines of a hexagram are in unstable positions away from the center, leading to the meaning of 'half-baked' or 'not on the right path.'
• Another explanation is that it simply means 'neither three nor four,' implying something that doesn't fit any standard category or is 'neither fish nor fowl.'
• The term is highly colloquial and carries a strong derogatory nuance. It is not used in formal settings or when speaking to superiors, but is common in parental scolding or gossip.

5. Similar and Opposite Idioms

• Similar Idioms:
  • 不伦不类 (bù lún bù lèi): Neither fish nor fowl; something that doesn't fit any category and looks ridiculous.
  • 非驴非马 (fēi lǘ fēi mǎ): Neither a donkey nor a horse; something strange and unclassifiable.
  • 不正之风 (bù zhèng zhī fēng): Unhealthy tendencies or practices.link
• Opposite Idioms:
  • 正人君子 (zhèng rén jūn zǐ): A person of integrity and honor; a true gentleman.
  • 堂堂正正 (táng táng zhèng zhèng): Dignified, open, and aboveboard in conduct.
  • 光明磊落 (guāng míng lěi luò): To be open and aboveboard in one's actions and character.link
  • 文质彬彬 (wén zhì bīn bīn): Refined in both manner and appearance.link

6. Summary

不三不四 (bù sān bù sì) is a colloquial expression used to criticize people or things that are suspicious, improper, or lack integrity. It is most commonly used to describe "shady characters," "improper relationships," or "indecent behavior." While frequent in daily conversation, it carries a strong negative tone and should be used with caution.