Le parquet est encore mouillé, fais attention.

Yes — parquet literally refers to wood flooring or parquet flooring, but in everyday French it can also simply mean the wooden floor.

So in this sentence, Le parquet est encore mouillé means The wooden floor is still wet.

A useful detail:

• le sol = the floor in general
• le parquet = a wooden floor specifically

Because mouillé agrees with le parquet, and parquet is a masculine singular noun.

So:

• le parquet → masculine singular
• adjective must match → mouillé

Compare:

• Le parquet est mouillé.
• La table est mouillée.

Here, encore means still.

So:

• Le parquet est encore mouillé = The floor is still wet

This is a very common use of encore.

Be careful: encore can also mean again in other contexts. For example:

• Dis-le encore. = Say it again.

So the meaning of encore depends on context.

Because fais attention is the imperative form — it is giving an instruction or warning: be careful.

The verb is faire. Its tu form in the present tense is:

• tu fais

In the imperative, French often uses the same verb form without the subject pronoun:

• Fais attention. = Be careful.

Compare:

• Tu fais attention. = You are being careful / You pay attention
• Fais attention ! = Be careful!

Because French imperatives normally drop the subject pronoun.

So instead of:

• Tu fais attention

you say:

• Fais attention !

This is normal for commands, warnings, and instructions.

Examples:

• Regarde ! = Look!
• Écoute ! = Listen!
• Prends ton temps. = Take your time.

Because the command is based on the tu form of faire, which is fais.

Present tense of faire:

• je fais
• tu fais
• il/elle fait

So:

• fais attention = command to one person
• fait attention would match il/elle fait, so it would not work as an imperative here

If you were speaking to several people or using vous, you would say:

• Faites attention.

Faire attention is a very common French expression meaning:

• to be careful
• to pay attention

In this sentence, it clearly means be careful because there is a danger: the floor is wet.

Examples:

• Fais attention ! = Be careful!
• Fais attention à la marche. = Watch out for the step.
• Il ne fait pas attention en classe. = He doesn’t pay attention in class.

Because fais attention can be used on its own as a complete warning.

You often add à when you specify what someone should watch out for:

• Fais attention au sol. = Watch out for the floor.
• Fais attention à la voiture. = Watch out for the car.

But if the danger is already clear from context, French often just says:

• Fais attention !

In this sentence, the first part already explains the danger:

• Le parquet est encore mouillé, fais attention.

So no à is necessary.

Yes, it is basically two linked clauses:

• Le parquet est encore mouillé
• fais attention

The comma connects a statement and a warning:

• The floor is still wet, be careful.

In French, this kind of punctuation is common in everyday writing. You could also write it as two separate sentences:

• Le parquet est encore mouillé. Fais attention.

Both are understandable.

Yes, if you are speaking to:

• more than one person, or
• one person in a formal way

then you would say:

• Le parquet est encore mouillé, faites attention.

So:

• fais attention = informal singular (tu)
• faites attention = formal singular or plural (vous)

Because mouillé is being used as a predicate adjective, not directly before the noun.

Structure:

• Le parquet = subject
• est = verb to be
• encore mouillé = adjective phrase

This is the same pattern as in English:

• The floor is wet

If you wanted the adjective directly with the noun, that would be a different structure, for example:

• le parquet mouillé = the wet floor

But here the sentence is saying what state the floor is in:

• Le parquet est encore mouillé.

A simple pronunciation guide is:

Le parquet est encore mouillé, fais attention.
≈ luh par-kay ay-tahn-kor moo-yay, fay ah-tahn-syohn

A few useful pronunciation notes:

• parquet sounds like par-kay
• est encore is often smoothly linked in speech
• mouillé sounds roughly like moo-yay
• fais sounds like fay
• attention sounds roughly like ah-tahn-syohn

The ll in mouillé does not sound like English l here; it gives a y sound.

It can describe both.

Examples:

• Le parquet est mouillé. = The floor is wet.
• Mes vêtements sont mouillés. = My clothes are wet.
• Je suis mouillé. = I’m wet. (said by a male speaker)
• Je suis mouillée. = I’m wet. (said by a female speaker)

So mouillé/mouillée is a very general adjective for wet.

Usually, encore is the better choice here.

• encore mouillé = still wet
• toujours mouillé can also mean always wet or sometimes still wet, but it is more ambiguous

So for a temporary continuing situation like a floor that has not dried yet, encore is the most natural word:

• Le parquet est encore mouillé.

Yes, it sounds completely natural.

It is the kind of thing someone might say at home, in a shop, in a hotel, or anywhere a recently cleaned floor could be slippery.

Very natural alternatives include:

• Le sol est encore mouillé, fais attention.
• Attention, le parquet est encore mouillé.
• Le parquet est mouillé, fais gaffe. (more informal)

But your original sentence is perfectly normal and clear.