cứ vs vẫn — Keep Doing (Urging vs Stating)

Quick Answer

[cứ is primarily used to encourage someone to continue an action, to "just" do something without hesitation, or to imply an arbitrary choice or continuation despite circumstances. It often carries a sense of permission or urging. Vẫn, on the other hand, simply states that an action or state "still" continues, often despite expectations, changes, or a previous condition, emphasizing persistence or an unchanging status.

Comparison Table

Detailed Explanation

Learning to distinguish between cứ and vẫn is key for A2 Vietnamese learners to express nuanced meanings related to continuity and persistence.

When to use cứ

Cứ is versatile and often used in situations where you want to encourage, permit, or instruct someone to proceed with an action without delay or hesitation. Think of it as conveying "just go ahead," "keep on," or "whatever you prefer, just do X."

• Urging or Permission: It tells someone to proceed freely. Example: Cứ làm đi! (Just do it! / Go ahead and do it!)
• Continuing an Action: It can mean to keep doing something, often in a repetitive or ongoing manner. Example: Cứ đợi ở đây nhé. (Just keep waiting here.)
• Conditional Situations: In 'if...then' structures (Nếu... thì cứ...), it suggests a default action to take. Example: Nếu bạn không hiểu, cứ hỏi tôi. (If you don't understand, just ask me.)
• Arbitrary Choice: It can imply a casual or unconcerned continuation, like "just do whatever." Example: Cứ theo ý bạn. (Just follow your own idea.)

When to use vẫn

Vẫn is used to state a factual continuation of a state or action. It means "still" or "yet" and often implies that something is ongoing despite a previous event, expectation, or change. Its Hán-Việt connection is 仍 (rēng) meaning "still" or "as before" in Chinese, which perfectly aligns with its Vietnamese usage.

• Persistence of a State/Action: It indicates that something continues to be true or occurs. Example: Anh ấy vẫn còn ngủ. (He is still sleeping.)
• Despite Expectations: Often used when an action or state persists contrary to what might be expected. Example: Trời mưa nhưng cô ấy vẫn đi làm. (It's raining but she still goes to work.)
• Unchanged Status: It highlights that something has not changed. Example: Tình hình vẫn như cũ. (The situation is still the same.)
• Negative Continuity (Still not/not yet): Frequently combined with chưa (not yet) to mean "still not." Example: Vẫn chưa xong. (Still not finished.)

Example Pairs

Common Patterns

• cứ... đi: This pattern is used for encouragement or permission. Example: Cứ thử đi! (Just try it! / Go ahead and try it!)
• cứ thế mà...: Means "just like that" or "keep doing that." Example: Cứ thế mà làm. (Just do it like that / Keep doing it that way.)
• nếu... thì cứ...: Used in conditional sentences to suggest a direct course of action. Example: Nếu bạn bận thì cứ về trước đi. (If you're busy, just go home first.)
• vẫn còn...: Expresses that something is "still remaining" or "still present." Example: Vẫn còn một ít. (There's still a little bit left.)
• vẫn chưa...: Means "still not" or "not yet." Example: Công việc vẫn chưa xong. (The work is still not finished.)
• mặc dù... nhưng vẫn...: This common construction highlights contrast: "although... but still..." Example: Mặc dù mệt nhưng anh ấy vẫn làm việc. (Although tired, he still works.)

Common Mistakes

Mistake 1 — Using vẫn for urging

Using vẫn when you intend to encourage or permit an action is incorrect because vẫn states a fact of continuity, not an imperative.

❌ Vẫn nói đi, đừng ngại.

✅ Cứ nói đi, đừng ngại.

Why it's wrong and how to fix it: "Vẫn nói đi" would literally mean "still speak" which doesn't convey the encouraging tone of "just speak up" or "go ahead and speak." Cứ is the correct word to give permission or encouragement.

Mistake 2 — Using cứ when simply stating a fact of continuity

Cứ implies an imperative, a sequence, or an arbitrary action, not a neutral statement of "still."

❌ Trời cứ mưa.

✅ Trời vẫn mưa.

Why it's wrong and how to fix it: While "Trời cứ mưa" could imply an annoying, continuous rain (like "it just keeps raining"), for a neutral statement simply meaning "it's still raining," vẫn is the appropriate choice. Vẫn clearly conveys that the state of raining persists.

Mistake 3 — Misusing in conditional permission

When offering a course of action based on a condition, cứ is used for permission or suggestion, while vẫn would imply an unlikely persistence.

❌ Nếu bạn mệt, bạn vẫn nghỉ ngơi đi.

✅ Nếu bạn mệt, bạn cứ nghỉ ngơi đi.

Why it's wrong and how to fix it: The incorrect sentence translates to "If you're tired, you still rest," which sounds illogical in English and Vietnamese. The correct sentence means "If you're tired, just go ahead and rest," using cứ to grant permission or suggest an action.

Related Grammar Points

• phải vs nên vs cần — Must vs Should vs Need (Comparison A2)
• vừa vs mới — Just (Emphasis vs Recent) (Comparison A2)
• gần vs cạnh vs bên cạnh — Near vs Next To vs Beside (Comparison A2)
• bằng — Equal Comparison (As...As) (Grammar A2)
• còn (still) vs còn (also) — Two Meanings of còn (Comparison A2)
• sắp vs gần — About To (Time vs Space/Time) (Comparison A2)

Quick Quiz

Fill in the blank with cứ or vẫn:

1. Tôi đã gọi anh ấy nhiều lần nhưng anh ấy _____ không trả lời.

Hint: The action of not answering is persisting despite calls.

2. Nếu bạn muốn đi chơi, bạn _____ đi đi!

Hint: This is an encouragement or permission.

3. Mặc dù trời đã sáng, nó _____ ngủ.

Hint: A state is persisting despite a change in conditions.