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不得而知 — pronunciations, definitions, and tags
HanziPinyinEnglishTags
不得而知bùdé’érzhīunknownHSK 7, unknown, 29 strokes, rank #21995, Very Hard
不得而知bùdé’érzhīunable to find outHSK 7, unknown, 29 strokes, rank #21995, Very Hard
bùdé’érzhī(bu4de2er2zhi1)bu de er zhi T4
  1. 1unknown
  2. 2unable to find out
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March 24, 2026

不得而知bùdé’érzhī(bu4de2er2zhi1)

不得而知 is an idiom that means something is unknown or cannot be determined. It is often used in contexts where information is lacking or when the truth of a situation is elusive, emphasizing the impossibility of knowing certain facts.

Strokes29Frequency#21995DifficultyVery Hard
Cultural note

This idiom reflects a common attitude in Chinese discourse, where uncertainty and the limits of knowledge are acknowledged, often seen in philosophical discussions or when addressing historical events.

Memory tip

Imagine a detective who cannot find the clues ('不得而知') to solve a mystery. The character 不 (bu) means 'not,' 得 (de) means 'obtain,' 而 (er) suggests 'and,' and 知 (zhi) means 'know.' Visualize the detective saying, 'I cannot obtain knowledge about this case!'

Meanings of 不得而知

bùdé’érzhī(bu4de2er2zhi1)
1unknown
2unable to find out
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About 不得而知

不得而知Simplified
29Strokes
—Radical
#—Frequency Rank
HSK 3.0L7AdvancedTOCFLL5CEFRC2

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AI study notes for 不得而知

Usage Notes

This idiom is typically used in formal contexts, such as academic writing or serious discussions. Common mistakes include using it in casual conversations, where simpler phrases would suffice. Be aware of the tone; it carries a sense of uncertainty rather than negative connotation.

HSK Study Tips

Although 不得而知 is not typically included in standard HSK levels, understanding it can enhance your comprehension of more complex written Chinese. Students should focus on idiomatic expressions and their nuances, as they often appear in advanced texts.

Common Mistakes

Learners often confuse 不得而知 with simpler phrases like '不知道' (bu zhi dao), which indicates a lack of knowledge but lacks the nuance of being unable to know. A common mistake is saying, '我不得而知这个问题,' which should be '我不知道这个问题.'

AI-enhanced 2026-03-24

Pronunciation of 不得而知

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Idiom spotlight: 不得而知

Chengyu origin story
Literal meaning:not obtain and know

Component characters

不bù(negative prefix)
HSK 14 strokes一
View full entry
得destructural particle: used after a verb (or adjective as main verb), linking it to following phrase indicating effect, degree, possibility etc
HSK 211 strokes彳
View full entry
而érand
HSK 46 strokes而
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知zhīto know
HSK 68 strokes矢
View full entry

How to say unknown in Chinese

“unknown” in Chinese is不得而知bùdé’érzhī

不得而知 is an idiom that means something is unknown or cannot be determined. It is often used in contexts where information is lacking or when the truth of a situation is elusive, emphasizing the impossibility of knowing certain facts.

When to use 不得而知

This idiom is typically used in formal contexts, such as academic writing or serious discussions. Common mistakes include using it in casual conversations, where simpler phrases would suffice. Be aware of the tone; it carries a sense of uncertainty rather than negative connotation.

What learners get wrong

Learners often confuse 不得而知 with simpler phrases like '不知道' (bu zhi dao), which indicates a lack of knowledge but lacks the nuance of being unable to know. A common mistake is saying, '我不得而知这个问题,' which should be '我不知道这个问题.'

Write 不得而知

不
得
而
知

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Frequently asked questions about 不得而知

It's better suited for formal contexts; in casual conversation, you might say '不知道' (bu zhi dao) instead.

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