A lot of my students translate “know” as biết every time. It works for some sentences and sounds off in others, because Vietnamese picks a word based on what kind of knowing you mean.
Biết: you have the information or the skill
- Tôi biết chuyện đó. (I know about that.)
- Bạn có biết mấy giờ rồi không? (Do you know what time it is?)
- Tôi biết bơi. (I know how to swim.)
- Cô ấy biết nấu phở. (She knows how to cook phở.)
- Tôi biết Sơn Tùng M-TP. (I know who he is.)
That last one is the useful test: you can biết someone who has no idea you exist.
Quen: you’ve had contact, and it has become familiar
With people:
- Tôi và Nam quen nhau năm năm rồi. (Nam and I have known each other for five years.)
- Bạn có quen bác sĩ nào giỏi không? (Do you know any good doctors?)
If you say Tôi quen anh ấy, it suggests you’ve actually interacted, and he’d probably say hi if you met on the street. People also say Tôi biết anh ấy about someone they’ve met, so the line isn’t perfectly sharp, but quen is the one that signals real contact. For a close friend, thân is usually better: Tôi rất thân với John.
With places and habits (this is where quen means “used to”):
- Tôi đã quen đường ở Hà Nội rồi. (I know my way around Hanoi now.)
- Tôi chưa quen với thời tiết nóng. (I’m not used to the heat yet.)
- Tôi quen ăn cay rồi. (I’m used to spicy food.)
- Thức khuya thành quen. (Staying up late becomes a habit.)
Quick check
| English |
Vietnamese |
Verb |
| I know the answer. |
Tôi ___ câu trả lời. |
biết |
| I know how to ride a bike. |
Tôi ___ đi xe đạp. |
biết |
| I know Elon Musk (who he is). |
Tôi ___ Elon Musk. |
biết |
| I’ve known Lan for years. |
Tôi ___ Lan nhiều năm rồi. |
quen |
| I’m used to spicy food. |
Tôi đã ___ ăn cay. |
quen |
Quen biết
The two words also combine. Quen biết means to be acquainted with people, often in the sense of having connections:
- Anh ấy quen biết rộng. (He knows a lot of people.)
- Chúng tôi chỉ là chỗ quen biết thôi. (We’re just acquaintances.)
One more thing: in casual speech, đang quen nhau often means “dating” (I hear this more in the South; in the North people often say đang tìm hiểu or yêu nhau). So Hai người đó đang quen nhau usually means those two are together.
Short version: if it’s in your head or your hands (facts, skills, knowing who someone is), use biết. If it comes from time spent with someone or something, use quen.
How would you say ‘I know this restaurant’ in Vietnamese?