Je nettoie le carrelage de la cuisine après le dîner.

In French, the present tense often covers both:

• I clean
• I am cleaning

So Je nettoie can mean either I clean or I am cleaning, depending on context.

French does have a way to emphasize right now, using être en train de:

• Je suis en train de nettoyer le carrelage... = I am in the middle of cleaning the tiles...

But in everyday French, the simple present Je nettoie is very common and natural.

Nettoie comes from the verb nettoyer = to clean.

This is the je form in the present tense:

• je nettoie
• tu nettoies
• il/elle nettoie
• nous nettoyons
• vous nettoyez
• ils/elles nettoient

You may notice the spelling change from y to i in several forms:

• nettoyer → je nettoie

This happens with many verbs ending in -yer.

French usually uses an article where English often does too, and sometimes where English might omit one.

Here, le carrelage means:

• the tiling
• the tiled floor
• the tiles

It refers to a specific thing: the kitchen tile surface.

So Je nettoie le carrelage is natural French for I clean the kitchen tiles / tiled floor.

Carrelage refers to tilework, tiling, or a tiled surface.

Depending on context, it could mean:

• the tile floor
• the tiles
• the tiling

In this sentence, it most likely means the kitchen tiled floor or kitchen tiles.

It is a bit more specific than sol:

• le sol = the floor
• le carrelage = the tiled floor / tile surface

So French is being more precise here.

De la cuisine means of the kitchen.

So:

• le carrelage de la cuisine = the kitchen tiles / the tiling of the kitchen

French often uses de + noun where English uses a noun directly as an adjective:

• kitchen floor → le sol de la cuisine
• kitchen table → la table de la cuisine

English stacks nouns together easily. French usually prefers de.

Because cuisine is a feminine noun:

• la cuisine = the kitchen

After de, the forms are:

• de + le → du
• de + la → de la
• de + l’ → de l’
• de + les → des

Since it is la cuisine, you get:

• de la cuisine

Not du cuisine.

Both can exist, but après le dîner is very natural and means after dinner / after the dinner meal.

French often uses the definite article with meals:

• le petit-déjeuner
• le déjeuner
• le dîner

So:

• après le dîner = after dinner

You may sometimes see après dîner in certain expressions or styles, but après le dîner is straightforward and common.

They are spelled the same, but they can have different roles:

• le dîner = dinner (noun)
• dîner = to have dinner / to dine (verb)

In your sentence:

• après le dîner

the word is a noun, because it follows le.

Examples:

• Je dîne à 19h. = I eat dinner at 7 p.m.
• Le dîner est prêt. = Dinner is ready.

French word order is often similar to English here.

The basic structure is:

• Je = subject
• nettoie = verb
• le carrelage de la cuisine = object
• après le dîner = time expression

Putting the time expression at the end is very natural:

• Je nettoie le carrelage de la cuisine après le dîner.

You could also move it for emphasis:

• Après le dîner, je nettoie le carrelage de la cuisine.

Both are correct.

Yes. The French present tense can describe:

• something happening right now
• something done regularly
• a general routine

So this sentence could mean:

• I am cleaning the kitchen tiles after dinner
  or
• I clean the kitchen tiles after dinner

Context tells you which meaning is intended.

A simple pronunciation guide is:

Je nettoie le carrelage de la cuisine après le dîner
→ zhuh neh-TWAH luh kah-reh-LAZH duh lah kwee-ZEEN ah-PREH luh dee-NAY

A few helpful notes:

• Je sounds like zhuh
• nettoie sounds roughly like neh-TWAH
• carrelage has the zh sound at the end
• cuisine sounds like kwee-ZEEN
• après sounds like ah-PREH
• dîner sounds like dee-NAY

Depending on speed and accent, je can sound very light in speech.

Yes, possibly, but there is a nuance.

• nettoyer = to clean
• laver = to wash

So:

• Je nettoie le carrelage... focuses on making it clean
• Je lave le carrelage... focuses more on washing it

In many real situations, both could work. But nettoyer is a bit broader and often the safer choice for clean.

Because je only becomes j’ before a word that starts with a vowel sound or a silent h:

• j’aime
• j’habite

But nettoie begins with n, so there is no elision:

• Je nettoie

Not J’nettoie in standard writing.