Ban công và sàn nhà có nhiều bụi.

In this sentence, có means something like there is / there are / has.

So Ban công và sàn nhà có nhiều bụi literally feels like:

• The balcony and the floor have a lot of dust
• or more naturally, There is a lot of dust on the balcony and the floor

Vietnamese often uses có to say that something exists in a place or that a place contains something.

Structure here:

• Ban công và sàn nhà = the balcony and the floor
• có = have / there is
• nhiều bụi = a lot of dust

Because bụi is mainly a noun here: dust.

So:

• nhiều bụi = a lot of dust

This is the most straightforward way to express the idea.

If you say rất bụi, that sounds more like treating bụi as an adjective, roughly very dusty. Some speakers may understand it, but có nhiều bụi is clearer and more standard for learners.

Compare:

• có nhiều bụi = there is a lot of dust
• rất bẩn = very dirty
• đầy bụi = full of dust / dusty

Sàn nhà means the floor of a house or room.

Breaking it down:

• sàn = floor surface
• nhà = house/home

Together, sàn nhà means the house floor / indoor floor.

Learners may also see:

• nền nhà = floor, especially the ground-level floor surface
• sàn = floor/platform in a broader sense

In this sentence, sàn nhà is a natural way to say the floor.

Vietnamese usually does not require articles like the, a, or an.

So:

• ban công can mean a balcony or the balcony
• sàn nhà can mean a floor or the floor
• bụi can mean dust in a general sense

The exact meaning depends on context. If the meaning has already been shown to the learner, then context tells you whether it is the balcony, the floor, or just those things in general.

This is very normal in Vietnamese.

It is written as two words, but it functions as one lexical item meaning balcony.

Vietnamese has many expressions like this: two written syllables that together form one word or fixed noun.

So you should learn ban công as one vocabulary item:

• ban công = balcony

You do not usually analyze it piece by piece in everyday learning.

Both patterns can work, but they focus slightly differently.

1. Ban công và sàn nhà có nhiều bụi

   • focuses on the balcony and the floor
   • literally: The balcony and the floor have a lot of dust

2. Có nhiều bụi trên ban công và sàn nhà

   • starts with the existence of dust
   • literally: There is a lot of dust on the balcony and the floor

So the original sentence is perfectly natural. It makes ban công và sàn nhà the subject/topic of the sentence.

Vietnamese often allows more than one natural way to express the same idea, depending on what you want to highlight.

Và means and.

So:

• Ban công và sàn nhà = the balcony and the floor

In many casual situations, Vietnamese can sometimes omit và when listing things, especially in speech, but with just two nouns like this, using và is the clearest and most standard choice.

For learners, it is best to keep và here.

No. Bụi does not need a classifier in this sentence.

Classifiers are common in Vietnamese when counting individual objects, for example:

• một cái bàn = one table
• hai con chó = two dogs

But bụi is a mass noun, like dust in English, so it is natural to say:

• nhiều bụi = a lot of dust

No classifier is needed.

Yes, it can.

Có nhiều bụi can describe the current condition:

• there is a lot of dust there right now

But depending on context, it can also imply a more general state:

• the balcony and floor tend to get dusty
• those areas are dusty

If you want a stronger descriptive feeling, Vietnamese might also use:

• rất bẩn = very dirty
• đầy bụi = dusty / full of dust

Still, the original sentence naturally communicates that those places have a lot of dust on them.

Bụi is pronounced roughly like boo-ee, but as one syllable, not two separate English syllables.

Important points:

• ụ is a short, back vowel, somewhat like oo
• i glides at the end
• the dot tone (nặng) makes it a low, short, heavy tone

So bụi has a clipped, heavy sound.

A rough learner-friendly guide:

• bụi ≈ booey said very quickly, with a low, heavy tone

It is much better to keep có here.

• Ban công và sàn nhà có nhiều bụi = natural
• Ban công và sàn nhà nhiều bụi = sounds incomplete or unnatural in standard Vietnamese

The word có is doing important grammatical work: it links the place/topic to the existence of dust.

So for this meaning, use:

• Ban công và sàn nhà có nhiều bụi