biết đâu
Who Knows
Biết đâu translates to "who knows," "perhaps," or "maybe." It is used to suggest a speculative, unexpected, or even contrary possibility without committing to how likely it is.
How It Works
While có thể states an objective probability and có lẽ implies a logical deduction, biết đâu acts as a "wildcard." It floats a hypothetical chance, often with a rhetorical flavor ("It seems unlikely, but who's to say?").
Key Collocations:
- Biết đâu lại + Verb: Emphasizes a surprising or contrary turn of events.
- Biết đâu đấy / Biết đâu được: Often used as a standalone exclamation meaning "Who knows!"
- Biết đâu chừng: A highly common variant that functions exactly the same way as biết đâu, acting as a direct synonym.
Important Nuances:
- Not just for wishful thinking: While often used for hopeful long-shots, it can also introduce neutral or unwanted possibilities (e.g., a sudden storm).
- Not a negation: Despite containing the word đâu (which is often used in denials), biết đâu in this context is an affirmative expression of possibility. Do not confuse it with the emphatic negative structure không biết đâu (I don't know at all).
Examples (5)
- Cứ thử nộp đơn đi, biết đâu lại trúng tuyển.
Just try applying; who knows, you might get accepted.
Word by Word: Continue try submit application go, know where again hit selection.
Pairs with 'lại' to highlight a hopeful but unexpected outcome.
- Trời đang nắng, nhưng biết đâu chiều lại mưa.
It's sunny now, but who knows, it might rain this afternoon.
Word by Word: Sky currently sunny, but know where afternoon again rain.
Demonstrates that 'biết đâu' can be used for unwanted or neutral surprises, not just positive ones.
- Biết đâu cô ấy sẽ đổi ý.
Perhaps she will change her mind.
Word by Word: Know where aunt that will change mind.
Placed at the beginning of the clause to introduce a speculative possibility.
- Anh ấy biết đâu lại là người chiến thắng.
Who knows, he might actually be the winner.
Word by Word: Brother that know where again is person win.
Placed immediately after the subject.
- Chuyện tương lai, biết đâu đấy!
The future, who knows!
Word by Word: Story future, know where there!
Used with 'đấy' as a standalone exclamation to mean 'Who knows!'
Common Mistakes
Translating 'biết đâu' literally as 'know where' when talking about locations.
Tôi không biết đâu anh ấy sống.Tôi không biết anh ấy sống ở đâu.Biết đâu is a fixed idiom meaning 'perhaps' or 'who knows.' When you want to say 'know where' regarding a location, you must separate the words: biết (know) + [Subject/Action] + ở đâu (where).
Reading 'biết đâu' as 'I don't know'.
Different MeaningBiết đâu anh ấy đến.Tôi không biết anh ấy có đến không.In this pattern, biết đâu is an affirmative expression of possibility: 'Biết đâu anh ấy đến' means 'maybe he will come'. To express a lack of knowledge, use standard negation like không biết.
How It Connects
Learn This First
The expression 'biết đâu' is a fixed idiomatic phrase combining the verb 'biết' (to know) and the question word 'đâu' (where). To understand how it functions as a marker of possibility, learners should first be familiar with the basic meanings of its component words.
Related Patterns
- có thểCan / Be Able to
While 'biết đâu' floats a speculative, unpredictable chance, 'có thể' is used for objective, factual probability or capability.
Level 1 - có lẽPerhaps
'Có lẽ' implies a logical deduction or a higher degree of likelihood ('perhaps/probably'), whereas 'biết đâu' implies a lower probability or a wildcard chance.
Level 3 - chắc làProbably
'Chắc là' expresses a strong assumption ('probably/likely'), contrasting with the low-commitment, rhetorical nature of 'biết đâu'.
Level 3 - ... đâuNot at All
The word 'đâu' is frequently used as a denial marker. Understanding this helps explain why learners often mistakenly think 'biết đâu' is a negative phrase.
Level 3
Words in This Pattern
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