Knowing and Understanding in Vietnamese

In Brief

Vietnamese divides English “know” among several verbs. Use biết for knowledge and learned skills, hiểu for understanding, and quen for being acquainted with a person or familiar with something. The key beginner pattern is biết + verb: Tôi biết nấu ăn means “I know how to cook.”

Overview

At A1, biết, hiểu, and quen let you handle many everyday situations: admitting that you do not know, checking whether someone understands, describing a skill, or saying that you know a person. They are ordinary Vietnamese verbs and do not change form for different subjects. Thus biết remains the same in tôi biết (“I know”), bạn biết (“you know”), and họ biết (“they know”).

The main difficulty for an English-speaking learner is that English “know” covers several relationships. We can know a fact, know how to cook, know a person, or know what a sentence means. Vietnamese usually asks you to choose the kind of knowing more precisely. A useful first rule is biết = have knowledge, hiểu = grasp the meaning, and quen = have familiarity through contact or experience.

The three verbs overlap at their edges, so context matters. For example, biết can identify someone you know of, while quen presents that person as an acquaintance. Start with the simple distinctions below; later sections explain these more subtle contrasts.

How It Works

The basic contrast

Verb	Core meaning	Typical object or complement	Example
biết	know, be aware; know how to	a fact, answer, person known of, or another verb	Tôi biết câu trả lời. — “I know the answer.”
hiểu	understand, grasp	words, meaning, a subject, a person’s point	Tôi hiểu câu này. — “I understand this sentence.”
quen	know personally; be familiar or accustomed	a person, or với + person/thing/situation	Tôi quen cô ấy. — “I know her personally.”

An object is the person or thing affected by or connected to the verb. In Tôi hiểu bài này, bài này (“this lesson”) is the object of hiểu.

Biết for facts and information

Use biết when someone possesses information or is aware of something:

• Subject + biết + noun: Tôi biết địa chỉ. — “I know the address.”
• Subject + biết + clause: Tôi biết anh ấy ở đâu. — “I know where he is.”
• Subject + biết + rằng + clause: Tôi biết rằng cô ấy bận. — “I know that she is busy.”

A clause is a group of words containing its own subject and verb. In Tôi biết cô ấy bận, the part cô ấy bận (“she is busy”) is what the speaker knows. Rằng introduces a statement much like English “that,” but it is often omitted in ordinary conversation.

For a simple negative, put không before the verb:

• Tôi không biết. — “I don’t know.”
• Anh ấy không biết địa chỉ. — “He doesn’t know the address.”

For a yes/no question, Vietnamese commonly places có before the verb and không after the object or complement:

• Bạn có biết cô Lan không? — “Do you know Ms. Lan?”
• Bạn có biết đường đến ga không? — “Do you know the way to the station?”

In conversation, a shorter verb + không? question is also common when the meaning is clear: Bạn biết không? (“Do you know?”).

Biết + verb for learned ability

Put another verb directly after biết to express a learned skill or knowledge of how to perform an action:

Subject + biết + action verb

• Tôi biết nấu ăn. — “I know how to cook.”
• Em bé biết đi rồi. — “The baby can walk now.”
• Bạn biết bơi không? — “Do you know how to swim?”

Vietnamese needs no equivalent of “how to” in this pattern. The second verb stays unchanged, just like biết.

This pattern is narrower than English “can.” Biết normally points to an acquired skill. For possibility, permission, or ability in the present circumstances, Vietnamese often uses có thể (“can, be able to”):

• Tôi biết lái xe. — “I know how to drive.” (I have the skill.)
• Hôm nay tôi không thể lái xe. — “I can’t drive today.” (Circumstances prevent it.)

Hiểu for meaning and comprehension

Use hiểu when the issue is whether someone grasps words, an idea, an explanation, or another person’s feelings:

• Subject + hiểu + object: Tôi hiểu bài học. — “I understand the lesson.”
• Subject + hiểu + clause: Tôi hiểu bạn muốn nói gì. — “I understand what you mean.”
• Subject + không hiểu: Tôi không hiểu. — “I don’t understand.”

The natural quick check Bạn hiểu không? means “Do you understand?” A fuller question, Bạn có hiểu không?, is also possible. Depending on tone and context, the shorter version may sound direct, so teachers and service staff may soften it with additional words such as Bạn có hiểu ý tôi không? (“Do you understand what I mean?”).

Knowing information and understanding it are not identical:

• Tôi biết quy tắc này, nhưng tôi chưa hiểu. — “I know this rule, but I don’t understand it yet.”

Here chưa means “not yet.” It is more precise than không when understanding may come later.

Quen for people and familiarity

Use quen + person when you are personally acquainted with someone:

• Tôi quen anh ấy. — “I know him / I’m acquainted with him.”
• Bạn có quen bác sĩ này không? — “Do you know this doctor personally?”

Use quen với + noun for familiarity or being accustomed to a thing, place, routine, or condition:

• Tôi quen với thành phố này. — “I’m familiar with this city.”
• Cô ấy chưa quen với thời tiết ở đây. — “She isn’t used to the weather here yet.”

With people, both quen anh ấy and quen với anh ấy occur. The version without với is a straightforward way to say that someone is an acquaintance. With situations and things, quen với is the safest general pattern for learners.

The difference between biết and quen with people

Both verbs can appear before a person’s name, but they present different kinds of knowledge:

• Tôi biết ca sĩ đó. — “I know of / know who that singer is.”
• Tôi quen ca sĩ đó. — “I know that singer personally.”

The contrast is not absolute in every context: biết can sometimes mean that you know a person, especially when the question is simply whether you can identify them. However, quen clearly emphasizes acquaintance or familiarity gained through contact. If you mean “I have met this person and we know each other,” quen is the more informative choice.

Examples in Context

Vietnamese	English	Note
Tôi biết nấu ăn.	I know how to cook.	biết + verb for a learned skill
Chị ấy biết nói tiếng Việt.	She knows how to speak Vietnamese.	Language ability
Tôi không biết.	I don’t know.	Complete everyday answer
Bạn có biết nhà vệ sinh ở đâu không?	Do you know where the restroom is?	biết + embedded question
Tôi biết anh Minh đang ở Hà Nội.	I know Minh is in Hanoi.	Knowledge of a fact
Bạn hiểu không?	Do you understand?	Short conversational question
Tôi hiểu câu này, nhưng không hiểu câu kia.	I understand this sentence, but not that one.	Contrast between two objects
Tôi chưa hiểu ý bạn.	I don’t understand your point yet.	chưa means “not yet”
Cô ấy hiểu tiếng Việt khá tốt.	She understands Vietnamese quite well.	Comprehension, not necessarily speaking ability
Tôi quen anh ấy.	I know him personally.	Personal acquaintance
Bạn có quen cô giáo mới không?	Do you know the new teacher personally?	có ... không question
Chúng tôi quen nhau ở trường đại học.	We got to know each other at university.	nhau indicates one another
Tôi chưa quen với công việc mới.	I’m not used to the new job yet.	Familiarity developed through experience
Dần dần, bạn sẽ quen.	Gradually, you’ll get used to it.	The context supplies what becomes familiar
Tôi biết quy tắc, nhưng chưa hiểu cách dùng.	I know the rule, but I don’t yet understand how to use it.	Clear biết/hiểu contrast

Common Mistakes

Using biết for every meaning of “know”

• Wrong: Tôi biết bài này. (when you mean that the lesson makes sense to you)
• Right: Tôi hiểu bài này.
• Why: Biết says that the lesson or information is known; hiểu says that you grasp its meaning. In some contexts both sentences are grammatical, but they answer different questions.

Using biết for a personal acquaintance without considering the nuance

• Less precise: Tôi biết anh ấy. (if you specifically mean that you know him personally)
• Clearer: Tôi quen anh ấy.
• Why: Biết can mean that you know who he is. Quen clearly expresses personal acquaintance.

Adding an English-style “how to” word after biết

• Wrong: Tôi biết cách nấu ăn. (if you simply mean “I know how to cook”)
• Natural: Tôi biết nấu ăn.
• Why: Biết + verb already expresses a learned skill. Biết cách nấu ăn is grammatical, but it emphasizes knowing the method or way of cooking rather than simply having the skill.

Confusing learned skill with present possibility

• Wrong meaning: Tôi không biết lái xe hôm nay. for “I can’t drive today.”
• Right: Hôm nay tôi không thể lái xe.
• Why: Không biết lái xe normally means you never learned to drive. Không thể expresses inability caused by the present situation.

Putting không after the verb in a negative statement

• Wrong: Tôi hiểu không câu này.
• Right: Tôi không hiểu câu này.
• Why: In a statement, không normally comes before the verb. Final không belongs to common yes/no question patterns: Bạn hiểu câu này không?

Omitting với in the basic “be used to” pattern

• Awkward for a beginner: Tôi chưa quen thời tiết này.
• Safer: Tôi chưa quen với thời tiết này.
• Why: When familiarity concerns a thing, condition, or environment, quen với + noun is the dependable general pattern.

Usage Notes

Talking about languages

The verb you choose shows what kind of language ability you mean:

• Tôi biết tiếng Việt. — “I know Vietnamese.” This is broad and context-dependent.
• Tôi biết nói tiếng Việt. — “I know how to speak Vietnamese.”
• Tôi hiểu tiếng Việt. — “I understand Vietnamese.”

If precision matters, name the skill: nói (speak), đọc (read), viết (write), or nghe (listen/understand by hearing). Someone may hiểu tiếng Việt without speaking it confidently.

Pronouns affect tone, not the verb form

Vietnamese pronouns often express age, relationship, and social role. You may hear Em hiểu không?, Anh có biết không?, or Cô có quen người này không? The choice among em, anh, cô, bạn, and others changes the social tone, but biết, hiểu, and quen do not conjugate.

Useful short responses

Everyday answers often omit material already clear from the question:

• Biết. — “Yes, I know.”
• Không biết. — “I don’t know.”
• Hiểu rồi. — “I understand now / Got it.”
• Chưa hiểu. — “I don’t understand yet.”
• Không quen. — “I don’t know them / I’m not familiar with it.”

Rồi here marks a new state: the speaker has now understood. These short replies are natural in context, though including an appropriate pronoun may sound more courteous in some interactions.

Beyond the Basics / Advanced Use

You do not need to master the following expressions at A1, but they show how the same verbs develop beyond the beginner rules.

Làm quen, quen nhau, and quen biết

Làm quen với means “get acquainted with” or “familiarize oneself with”:

• Tôi muốn làm quen với mọi người. — “I want to get to know everyone.”
• Bạn cần làm quen với hệ thống mới. — “You need to familiarize yourself with the new system.”

Quen nhau describes people knowing one another and can refer either to becoming acquainted or to an existing relationship, depending on the sentence: Chúng tôi quen nhau từ năm ngoái (“We have known each other since last year”). In some contexts, especially when discussing two people, quen nhau can also suggest dating; the wider context makes the intended relationship clear.

Quen biết is a compound expression meaning “be acquainted” or “have connections”: Tôi không quen biết ai ở đây (“I don’t know anyone here”). It often sounds broader than naming one simple acquaintance.

Biết được and discoveries

Biết được often presents knowledge as obtained, discovered, or made possible:

• Tôi mới biết được tin này. — “I only just found out this news.”
• Làm sao bạn biết được? — “How could you know?” / “How did you find out?”

Its exact force depends on context. Beginners can continue using plain biết while learning to recognize biết được in speech and writing.

Degrees of understanding

Vietnamese can refine hiểu with complements and adverbs:

• hiểu rõ — understand clearly or thoroughly
• hiểu sai — misunderstand
• hiểu lầm — misunderstand, often about a person or intention
• hiểu sâu — understand deeply

For example, Bạn hiểu lầm ý tôi rồi means “You have misunderstood what I meant.” These combinations are more precise than merely saying không hiểu.

Being accustomed to an action

For habitual familiarity, you may see quen với việc + verb, where việc turns an action into an activity that can follow với:

• Tôi quen với việc dậy sớm. — “I’m used to getting up early.”

Spoken Vietnamese may use shorter alternatives, including quen + verb in suitable contexts. Quen với việc + verb is a clear, explicit pattern for formal or careful language.

Practice Tips

1. Sort English “know” sentences by meaning. Take ten short sentences and label each one “information,” “understanding,” “skill,” or “acquaintance.” Then choose biết, hiểu, or quen before translating.
2. Build three reusable question frames: Bạn có biết ... không?, Bạn hiểu ... không?, and Bạn có quen ... không? Replace the missing part with places, sentences, people, and everyday information.
3. Contrast skill and circumstance aloud. Pair Tôi biết bơi (“I know how to swim”) with Hôm nay tôi không thể bơi (“I can’t swim today”). This prevents the common habit of using biết for every English “can.”

Related Concepts

• Prerequisite: Basic Verb Structure — explains unchanged Vietnamese verb forms, basic word order, negation, and tense markers.