Quick Answer
Both Cũng and Đều can translate to "also" or "too" in some English contexts, but they carry distinct meanings in Vietnamese. Cũng typically means "also" or "as well," showing addition or agreement for one or more subjects. Đều means "all," "both," or "evenly," indicating that something applies universally to every member of a group.
Comparison Table
| Feature | Cũng (also, too) | Đều (all, both, evenly) |
|---|---|---|
| Meaning | Expresses addition, similarity, agreement. "Also," "too," "as well," "even." | Expresses universality, equality, distribution. "All," "both," "evenly," "equally." |
| Subject focus | Can apply to one subject or multiple subjects individually. | Applies to all members of a plural subject collectively. |
| Number of subjects | Usually used with one subject, or with multiple subjects where each performs the action. | Always used with a plural subject (two or more). |
| Position | Usually before the verb/adjective. | Usually before the verb/adjective. |
| Example 1 |
Anh ấy cũng là giáo viên. He is also a teacher. |
Tất cả học sinh đều thích môn Toán. All students all like Math. |
| Example 2 |
Tôi cũng muốn đi. I also want to go. |
Chúng tôi đều muốn đi. All of us want to go. |
Detailed Explanation
Understanding the difference between Cũng and Đều is key to sounding natural in Vietnamese. While both can appear in contexts where English might use "also" or "too," their underlying grammatical function is different.
Cũng is used to show addition, similarity, or agreement. Think of it as linking two pieces of information. If someone says "I like coffee," and you also like coffee, you would say "Tôi cũng thích cà phê." It can be used for a single subject or for multiple subjects where the action or state is true for each one individually, similar to saying "A, and B also..."
Đều, on the other hand, emphasizes that an action, state, or quality applies to every single member of a group. It means "all," "both," "equally," or "evenly." It highlights the universality of the statement within a plural subject. If you have a group of friends, and every one of them is busy, you'd say "Chúng tôi đều bận." It can often be translated as "all (of us/them)" or "both." The word đều (均) has a Hán-Việt connection to the Chinese character meaning "equal" or "even," which helps explain its meaning of universality and equal application.
A good way to remember is: if you're adding something to a list or agreeing with a statement, use cũng. If you're talking about a characteristic or action that applies to everyone in a specific group, use đều.
Example Pairs
1a. Tôi thích phở. Anh ấy cũng thích phở.
I like pho. He also likes pho.
1b. Lan và Mai đều thích phở.
Lan and Mai both like pho.
2a. Hôm nay trời mưa. Ngày mai trời cũng mưa.
It's raining today. It will also rain tomorrow.
2b. Cả hai ngày đều mưa.
Both days rained.
3a. Cô ấy là bác sĩ. Chị gái cô ấy cũng là bác sĩ.
She is a doctor. Her older sister is also a doctor.
3b. Hai chị em họ đều là bác sĩ.
The two sisters are both doctors.
4a. Tôi nói tiếng Việt. Bạn cũng nói tiếng Việt.
I speak Vietnamese. You also speak Vietnamese.
4b. Chúng ta đều nói tiếng Việt.
We all speak Vietnamese.
5a. Món ăn này ngon. Món kia cũng ngon.
This dish is delicious. That dish is also delicious.
5b. Hai món ăn này đều ngon.
Both of these dishes are delicious.
6a. Tôi đi chợ. Mẹ tôi cũng đi chợ.
I go to the market. My mother also goes to the market.
6b. Chúng tôi đều đi chợ.
We all go to the market.
7a. Anh ấy đã về. Cô ấy cũng đã về.
He has returned. She has also returned.
7b. Họ đều đã về.
They have all returned.
8a. Em bé đang ngủ. Chị nó cũng đang ngủ.
The baby is sleeping. Its sister is also sleeping.
8b. Hai đứa trẻ đều đang ngủ.
The two children are both sleeping.
Common Patterns
Cũng + Verb/Adjective: To express "also do/be something" (for a single or individually-acting subject).
Tôi cũng mệt.
I am also tired.
Subject (plural) + Đều + Verb/Adjective: To express "all/both do/be something" (for an entire group).
Họ đều là người Việt Nam.
They are all Vietnamese.
Cả... Đều: "Cả" (all, whole) often precedes a plural subject and is frequently paired with đều to emphasize universality.
Cả nhà tôi đều thích ăn rau.
My whole family all like eating vegetables.
Common Mistakes
Mistake 1 — Using Đều with a singular subject
Đều always implies a plurality – two or more items or people. Using it with a singular subject makes the sentence grammatically incorrect.
❌ Anh ấy đều là học sinh.
✅ Anh ấy cũng là học sinh.
Why it's wrong and how to fix it: "Anh ấy" is singular. If you mean "He is also a student" (like someone else), you need cũng. Đều would imply he is "all" students, which doesn't make sense.
Mistake 2 — Using Cũng when meaning 'all' for a group
While cũng can sometimes be used with multiple subjects (e.g., "A and B cũng..."), it doesn't carry the strong sense of universality that đều does. If you mean "every single one of them," đều is almost always preferred.
❌ Chúng tôi cũng nói tiếng Anh.
✅ Chúng tôi đều nói tiếng Anh.
Why it's wrong and how to fix it: If you intend to say "We all speak English" (meaning every person in 'chúng tôi'), then đều is correct. "Chúng tôi cũng nói tiếng Anh" could mean "We also speak English (in addition to another language)" or "We also speak English (like someone else does)," but not necessarily "all of us."
Mistake 3 — Omitting Cả when it clarifies the group with Đều
While not strictly a mistake, sometimes omitting "cả" before a plural subject with "đều" can make the universality less explicit, especially when the plural is not explicitly stated (e.g., just "họ").
❌ Người dân thích ngày Tết đều.
✅ Cả người dân đều thích ngày Tết.
Why it's wrong and how to fix it: The original sentence is a bit awkward. Adding Cả ("all the") before the subject "người dân" (people) and keeping đều reinforces that all people like Tết, making the sentence much more natural and clear.
Quick Quiz
Fill in the blank with cũng or đều:
- Tôi muốn ăn cơm. Anh ấy _____ muốn ăn cơm.
Hint: This shows an addition to what someone else wants.
Answer
Correct answer: Tôi muốn ăn cơm. Anh ấy cũng muốn ăn cơm.
Explanation: "Cũng" is used here to indicate that "he" (anh ấy) also wants to eat rice, just like "I" (tôi) do. It's an agreement or addition.
- Ba chị em họ _____ rất xinh đẹp.
Hint: This describes a quality true for every member of the group of three sisters.
Answer
Correct answer: Ba chị em họ đều rất xinh đẹp.
Explanation: "Đều" is used because the statement applies to all three sisters (ba chị em họ) collectively, meaning "all of them are very beautiful."
- Tôi không thích cà phê. Em gái tôi _____ không thích cà phê.
Hint: This is about a shared dislike, an addition to a negative statement.
Answer
Correct answer: Tôi không thích cà phê. Em gái tôi cũng không thích cà phê.
Explanation: "Cũng" is used to show that "my sister" (em gái tôi) also doesn't like coffee, just like "I" (tôi). It's an agreement in a negative context.