Phòng đã đầy người.

In this sentence, đã means something like already.

So Phòng đã đầy người suggests that the room has already become full of people, or that this state has already happened.

A very important point for English speakers: đã does not always translate as a simple past tense marker. It often marks a change that has occurred by now.

So depending on context, this sentence could mean things like:

• The room is already full of people.
• The room has become full of people already.

It focuses on the fact that the room has reached that state.

Vietnamese often does not use a separate verb meaning to be in sentences like this.

In Phòng đã đầy người:

• Phòng = room
• đã = already
• đầy người = full of people / crowded with people

Here, đầy works as a predicate, so Vietnamese does not need a word equivalent to English is.

A very literal breakdown would be:

• Room already full people

That is completely normal Vietnamese structure.

đầy người means full of people or crowded with people.

The key word is đầy, which means full. When followed by a noun, it often means full of ...

Examples:

• đầy nước = full of water
• đầy xe = full of vehicles
• đầy người = full of people

In natural English, đầy người is often better translated as:

• crowded
• packed with people
• full of people

So the whole sentence gives the idea that the room is packed.

Because đầy + noun is a common Vietnamese pattern meaning full of + noun.

So:

• đầy người = full of people
• đầy sách = full of books
• đầy bụi = full of dust

English usually needs of here, but Vietnamese does not. The noun can come directly after đầy.

So đầy người is perfectly normal grammar, not a shortened version of something longer.

It is best understood as describing a current state, but with emphasis that the state has already been reached.

So although đã can sometimes point to the past, in this sentence the meaning is often closer to:

• The room is already full of people.

rather than simply:

• The room was full of people.

Why? Because đầy describes the room’s current condition, and đã tells us that this condition has already happened.

So this is often more about resulting state than pure past time.

Yes. You could say:

• Phòng đầy người.

That means simply:

• The room is full of people.

Adding đã changes the nuance. It adds the sense of already:

• Phòng đầy người. = The room is full of people.
• Phòng đã đầy người. = The room is already full of people.

So đã makes the statement feel more time-sensitive or more like a change has occurred.

Both đã and rồi can express the idea of already, but they are not used in exactly the same way.

For this sentence, you might hear:

• Phòng đã đầy người.
• Phòng đầy người rồi.
• Phòng đã đầy người rồi.

General idea:

• đã often marks that something has occurred or reached a state
• rồi often emphasizes that the result is now in place

Very roughly:

• đã = already / has
• rồi = already / now / by now

In many everyday cases, Phòng đầy người rồi sounds very natural and conversational: The room is full already.

Using both together can sound even more explicit or emphatic.

Vietnamese does not use articles like a, an, or the the way English does.

So phòng can mean:

• a room
• the room
• room

depending on context.

If the context is clear, Phòng đã đầy người is perfectly natural.

Sometimes Vietnamese can use a fuller noun phrase, such as:

• Căn phòng đã đầy người.

Here, căn is a classifier often used for rooms, houses, and similar enclosed spaces. This version can sound a bit more explicit or descriptive.

But in many cases, just phòng is fine.

Both are natural, but they are slightly different.

• đầy người = full of people, packed with people
• đông người = crowded, populous, having many people

So:

• Phòng đầy người gives the image that the room is filled up with people
• Phòng đông người means there are many people in the room, but it may sound a little less strongly like the room is packed to capacity

If you want the idea of the room has filled up, đầy người is especially good.

Yes. For learners, it is helpful to think of đầy here as an adjective meaning full.

In Vietnamese, adjectives can often function directly as the main predicate of a sentence.

So this pattern is normal:

• Phòng rộng. = The room is spacious.
• Phòng vắng. = The room is empty / quiet.
• Phòng đầy người. = The room is full of people.

That is why Vietnamese does not need a separate word for is before đầy.

Not exactly the same, though it is related.

• Phòng đã đầy. = The room is already full.
• Phòng đã đầy người. = The room is already full of people.

The version with người is more specific. It tells you what the room is full of.

Without người, the sentence is more general. The room could be full of people, objects, furniture, or something else, depending on context.

It is basically neutral and natural Vietnamese.

It would work in everyday conversation and in normal written language.

For example, someone might say it when talking about an event:

• Mình vào sau nhé, phòng đã đầy người.
• Let’s go in later; the room is already full of people.

It is not slang, and it is not especially formal either.

Yes, in some contexts that is a very reasonable English translation.

Because đã can highlight that a state has been reached, the sentence can suggest a change:

• the room was not full before
• now it has become full of people

So depending on context, English translations could include:

• The room is already full of people.
• The room has filled up with people.
• The room has already become crowded.

The best translation depends on whether you want to emphasize the current state or the change into that state.