Le médiateur national de l’énergie examine la facture d’électricité.

Because énergie is a feminine noun and it begins with a vowel sound.

Normally:

• de + le = du
• de + la = de la

But before a vowel, de la becomes de l’ for ease of pronunciation.

So:

• de la énergie → de l’énergie

You would use du with a masculine singular noun beginning with a consonant, such as du pain.

For the same reason: French avoids de directly before a vowel.

So:

• de électricité becomes d’électricité

This is called elision. The final vowel of de drops before a vowel or silent h.

Other examples:

• d’eau
• d’argent
• d’habitude

Because facture is a feminine singular noun, so it takes the feminine singular definite article la.

French articles must agree with the noun:

• le = masculine singular
• la = feminine singular
• les = plural

So:

• la facture
• le médiateur

Because after de, French often leaves out the article when the second noun is being used to describe the type, purpose, or category of the first noun.

So facture d’électricité means an electricity bill, with électricité functioning like a describing noun.

Compare:

• une tasse de thé
• une salle de classe
• une facture d’électricité

But French does not always omit the article after de. In de l’énergie, the article stays because it refers to the field or domain of energy more specifically.

French usually does not stack nouns together as easily as English does.

English often says:

• energy mediator
• electricity bill

French more often uses de to link nouns:

• médiateur de l’énergie
• facture d’électricité

So de is one of the main ways French expresses relationships that English often shows with noun + noun combinations.

Because many French adjectives come after the noun, and national is one of them in this context.

So:

• un médiateur national

This is very normal in French. English often puts adjectives before the noun, but French frequently places them after it.

Compare:

• un service public
• une politique nationale
• un médiateur national

If the noun were feminine, the adjective would also change:

• une médiatrice nationale

Examine is the third-person singular present tense of the verb examiner.

Conjugation:

• j’examine
• tu examines
• il/elle examine
• nous examinons
• vous examinez
• ils/elles examinent

In the sentence, the subject is Le médiateur national de l’énergie, which is singular, so the verb is examine.

Notice that the infinitive is examiner, not examine.

French verb endings work differently from English ones.

In writing, French does mark person and number, but many endings are not pronounced clearly or are completely silent.

For examiner in the present tense:

• j’examine
• tu examines
• il examine
• ils examinent

These forms can sound very similar, so French relies heavily on the subject pronoun or noun phrase:

• je
• tu
• il/elle
• ils/elles

That is why the full subject Le médiateur national de l’énergie is important.

Yes, they matter. Accents are a normal part of French spelling and often affect pronunciation.

Here, the é usually gives a sound like ay in English:

• médiateur
• énergie
• électricité

You should treat the accent as part of the word, not as an optional mark. Writing energie instead of énergie is considered a spelling mistake in normal French.

French uses capital letters more sparingly than English.

Even in official names or titles, common nouns such as médiateur, national, and énergie are often written in lowercase unless there is a specific stylistic reason to capitalize them.

So lowercase in:

• Le médiateur national de l’énergie

is completely normal French usage.

Yes. If the mediator is female, you would normally use the feminine form:

• La médiatrice nationale de l’énergie examine la facture d’électricité.

Changes:

• Le → La
• médiateur → médiatrice
• national → nationale

French nouns and adjectives often change form to match gender.

Because this sentence follows a very common French pattern:

Subject + verb + object

• Le médiateur national de l’énergie = subject
• examine = verb
• la facture d’électricité = object

French and English often share this basic word order in straightforward statements, even though other details, like adjective placement and noun linking with de, are different.

It is part of the noun phrase describing which mediator we are talking about.

The full subject is:

Le médiateur national de l’énergie

You can think of it as:

• the mediator
• specifically, the national mediator
• specifically, the national mediator for energy

So de l’énergie is linked to médiateur, not to the verb examine.

The main noun is médiateur.

Everything else adds information about it:

• Le = the article
• médiateur = the core noun
• national = adjective describing the mediator
• de l’énergie = complement specifying the area or domain

A useful strategy is to find the word that would still make sense if the rest were removed:

• Le médiateur examine la facture.

That shows you that médiateur is the main noun and examine is the main verb.