Chúng tôi chúc cô ấy luôn vui.

A simple breakdown is:

• Chúng tôi = we/us, excluding the listener
• chúc = wish
• cô ấy = her / she, literally that cô
• luôn = always
• vui = happy, cheerful

So the sentence is literally something like We wish her always happy.
In natural English, you would usually say We wish her to always be happy or simply We wish her happiness.

Vietnamese makes a distinction that English does not:

• chúng tôi = we, but not including the person being spoken to
• chúng ta = we, including the person being spoken to

So chúng tôi is used when the speaker means we as a group separate from the listener. That is a very common point for English speakers, because English we can mean either one.

Cô ấy is a third-person reference to a woman, usually translated as she or her.

The word cô can refer to different kinds of women depending on context, such as:

• a younger or middle-aged woman
• an aunt
• a female teacher
• a respectful way to refer to a woman in a certain age/status range

When ấy is added, it turns it into that cô, which works like she/her in English.

So in this sentence, cô ấy is the person receiving the wish.

Ấy helps mark the person as that person over there / the one we are talking about, so it often functions like a third-person marker.

Compare:

• cô = woman / aunt / teacher / you, depending on context
• cô ấy = that woman, meaning she/her

This pattern is very common in Vietnamese:

• anh ấy = he / him
• chị ấy = she / her
• ông ấy = he / him for an older man
• bà ấy = she / her for an older woman

Without ấy, cô could sound like direct address or just a noun, not clearly she/her.

Because Vietnamese often does not use a copula like English to be before adjectives or stative descriptions.

In English:

• She is happy

In Vietnamese:

• Cô ấy vui

There is no need for a separate word meaning is here.

So in chúc cô ấy luôn vui, the meaning is essentially wish her always happy, with the idea of to be understood automatically.

For English speakers, the easiest way to think of vui is as an adjective meaning happy or cheerful.

But in Vietnamese grammar, words like vui often behave like stative verbs as well. That is why they can be used directly as the predicate without to be.

So:

• cô ấy vui = she is happy
• chúc cô ấy luôn vui = wish her always happy / wish her always to be happy

You do not need to force a strict English-style adjective/verb distinction every time.

Because luôn is an adverb meaning always, and it normally comes before the verb or adjective it modifies.

So:

• luôn vui = always happy

This is the normal order.

You may also hear luôn luôn, which is just a stronger or fuller form:

• luôn vui
• luôn luôn vui

Both are possible, but luôn vui is shorter and very natural.

Chúc means to wish someone something good.

It is commonly used for greetings, blessings, and good wishes:

• Chúc mừng năm mới = Happy New Year
• Chúc em ngủ ngon = I wish you a good sleep / Sleep well
• Chúc anh may mắn = I wish you good luck

A very common pattern is:

• chúc + person + good state/result

So in this sentence:

• chúc cô ấy luôn vui = wish her always to be happy

This is not the same as English wish in the sense of want. For want, Vietnamese usually uses muốn.

Yes, Chúng tôi chúc cô ấy luôn vui is natural and understandable.

That said, Vietnamese often uses slightly fuller expressions in warm wishes, such as:

• luôn vui vẻ = always cheerful
• luôn hạnh phúc = always happy, in a deeper sense
• luôn vui khỏe = always happy and healthy

So these are all natural:

• Chúng tôi chúc cô ấy luôn vui
• Chúng tôi chúc cô ấy luôn vui vẻ
• Chúng tôi chúc cô ấy luôn hạnh phúc

The version with just vui is short, simple, and perfectly fine.

Yes.

If you are talking about her, you say:

• cô ấy = she/her

If you are talking to her, you would normally just say:

• cô

So:

• Chúng tôi chúc cô ấy luôn vui = We wish her always to be happy
• Chúng tôi chúc cô luôn vui = We wish you always to be happy

Using cô ấy to address her directly would sound wrong, because ấy marks someone being talked about, not the person being spoken to.

Not explicitly.

Vietnamese often leaves tense unmarked when the meaning is already clear from context. Here, the sentence expresses a wish being made now, but the hoped-for result is ongoing or future:

• chúng tôi chúc... = we wish...
• luôn vui = always happy

So the sentence does not need a special future marker. The idea of a future or continuing wish is understood naturally.

A rough learner-friendly guide is:

• Chúng = like choong with a rising-glottal kind of tone depending on dialect
• tôi = roughly toy
• chúc = roughly chook
• cô = roughly koh
• ấy = roughly ay, with a rising tone
• luôn = roughly loo-uhn or luohn
• vui = roughly voo-ee blended together

A few important points:

• ch in chúng, chúc is not exactly English ch in every dialect, but that approximation is okay at first.
• ô in tôi and cô is a rounded vowel; try not to make it too flat.
• vui is one syllable, not two separate English syllables.
• The tones matter a lot, so it is best to learn them from native audio if possible.