Le centre de contrôle technique ouvre aujourd’hui.

In French, nouns are very often used with an article. Le centre means the center.
Unlike English, French usually does not drop the article in a sentence like this.

So:

• Le centre ouvre aujourd’hui. = The center opens today.

Using just centre by itself would usually sound incomplete here.

Here, de links one noun to another, a bit like of or sometimes just a noun modifier in English.

So:

• centre de contrôle = center of inspection/checking
• contrôle technique = technical inspection

French often uses de + noun where English uses a compound noun:

• salle de classe = classroom
• bureau de poste = post office

So centre de contrôle technique is a natural French noun phrase built step by step.

In French, adjectives usually come after the noun they describe.

Here:

• contrôle = inspection/check
• technique = technical

So:

• contrôle technique = technical inspection

This is the normal order in French.
English often puts the adjective first, but French usually puts it after the noun.

Ouvre is the third person singular present tense form of the verb ouvrir (to open).

The subject is Le centre, which is singular, so French uses:

• j’ouvre = I open
• tu ouvres = you open
• il / elle / on ouvre = he / she / one opens
• le centre ouvre = the center opens

So ouvre agrees with the singular subject le centre.

Because ouvre already means opens.
French does not need a separate is here.

Compare:

• The center opens today.
• Le centre ouvre aujourd’hui.

If you said is opening in English, French might use the simple present anyway, depending on context. French often uses the present tense where English might use either opens or is opening.

Most directly, it means opens. But depending on context, English might translate it as:

• opens today
• is opening today

French present tense can cover both a simple present and a present-in-progress idea more often than English does.
So the exact English wording depends on context, but the French form stays ouvre.

Because aujourd’hui comes from older French elements that were joined together over time. In modern French, you should simply learn it as the fixed word meaning today.

A helpful point for learners: treat aujourd’hui as one expression, not as something you need to build yourself each time.

Also notice the accent in aujourd’hui does not change the basic meaning; it is just part of the correct spelling.

A rough English-friendly guide:

• Le ≈ luh
• centre ≈ sahntr
• de ≈ duh
• contrôle ≈ kohn-trohl
• technique ≈ tek-neek
• ouvre ≈ oovr
• aujourd’hui ≈ oh-zhoor-dwee

A few pronunciation notes:

• French r is not the same as English r.
• ou sounds like oo in food.
• eu in le is not a normal English sound; luh is only an approximation.
• The final consonants are often softer than in English.

Because the subject is singular:

• Le centre = the center

So the verb must also be singular:

• Le centre ouvre

If the subject were plural, you would use ouvrent:

• Les centres ouvrent aujourd’hui. = The centers open today.

Yes, very often it is. In everyday French, contrôle technique commonly refers to an official vehicle inspection, especially for cars.

So depending on context, centre de contrôle technique may specifically mean a place where vehicles are inspected.

That is useful because sometimes a phrase is grammatically transparent, but it also has a specific real-world meaning that learners should know.

Yes, but it means something slightly different.

• Le centre de contrôle technique ouvre aujourd’hui = the center opens today / is opening today
• Le centre de contrôle technique est ouvert aujourd’hui = the center is open today

The first focuses on the event or fact of opening.
The second focuses on the state of being open.

In many real situations, both could be possible, but they are not exactly the same idea.