Marie leur apporte du pain et du fromage quand ils viennent.

Leur is an indirect object pronoun meaning to them.

• It replaces à eux / à elles.
• It refers to a group of people already known from the context.
• In this sentence, it most naturally refers to the same people as ils (the ones who come), so: Marie brings them bread and cheese when they come.

In French, object pronouns normally go before the conjugated verb in simple tenses:

• Marie leur apporte… = Marie brings them…

The standard order is: subject + object pronoun(s) + verb + (rest of the sentence)

So:

• ✅ Marie leur apporte du pain.
• ❌ Marie apporte leur du pain. (wrong order)

• leur = indirect object pronoun, meaning to them
• les = direct object pronoun, meaning them

The verb apporter is used like this:

• apporter quelque chose à quelqu’un
  (to bring something to someone)

Because of the à quelqu’un, the people are an indirect object, so you need leur.

Compare:

• Marie leur apporte du pain.
  Marie brings them bread. (brings bread to them)
• Marie les apporte.
  Marie brings them. (here “them” would be the things, e.g. the breads/cheeses, as direct objects)

Leur and eux are different types of pronouns:

• leur = unstressed indirect object pronoun (to them)
  → must go before the verb: Marie leur apporte…

• eux = stressed (disjunctive) pronoun (them for emphasis, after prepositions, alone, etc.)
  → used in positions like:

  • avec eux (with them)
  • chez eux (at their place)
  • Pour eux, c’est important. (For them, it’s important.)
  • C’est à eux. (It belongs to them.)

You can combine them for emphasis:

• Marie leur apporte du pain, à eux.
  (Marie brings bread to them, not to others.)

But on its own before the verb, you must use leur, not eux.

The verb agrees with the subject, not with leur.

• Subject = Marie → 3rd person singular
• So the verb must be apporte.

Leur is just an object pronoun and doesn’t affect the verb ending.

• ✅ Marie leur apporte du pain.
• ❌ Marie leur apportent du pain. (wrong, plural verb with singular subject)

Yes, you could, but the meaning shifts slightly:

• apporter = to bring (an object) to someone/somewhere
  Focus on movement of a thing toward a place/person.
  → Best choice with du pain et du fromage.

• donner = to give
  Focus on handing something over, not on the movement.
  → Marie leur donne du pain et du fromage = She gives them bread and cheese.

• amener = to bring (a person or animal)
  Normally used for people/animals, not inanimate objects.
  → Marie amène les enfants (Marie brings the children),
  but amener du pain sounds odd.

So apporter is the natural, idiomatic choice here.

Du here is the partitive article (de + le) and means some.

French normally needs an article in front of a noun. For an unspecified quantity of a mass noun like bread, you use the partitive:

• du pain = (some) bread
• de la confiture = (some) jam
• de l’eau = (some) water

Alternatives:

• le pain = the bread (a specific bread, or bread in general as an abstract category)
• Just pain without an article is not correct in this context.

Again, du fromage is the partitive: some cheese (an unspecified amount).

• du fromage = some cheese (mass, uncountable sense)
• des fromages = some cheeses (several cheeses, often different types or individual cheeses)

So:

• Marie leur apporte du fromage.
  → She brings them (some) cheese.

• Marie leur apporte des fromages.
  → She brings them several cheeses / various cheeses.

In standard French, you should repeat the article:

• ✅ Marie leur apporte du pain et du fromage.
• ❌ Marie leur apporte du pain et fromage. (sounds incorrect or very careless)

Each noun in a list normally keeps its own article. Dropping the second du in this case is not considered correct in careful French.

With the present tense, quand ils viennent expresses a general, repeated habit:

• Marie leur apporte du pain et du fromage quand ils viennent.
  ≈ “Marie brings them bread and cheese when(ever) they come (over).”

It doesn’t describe one specific visit or a single future event, but what usually happens whenever they come.

Because the sentence describes a habit, not a single future situation. In French:

• Habitual/general fact → present + present
  Marie leur apporte du pain quand ils viennent.

If you were talking about a specific future event, you would normally use the future in both clauses:

• Marie leur apportera du pain et du fromage quand ils viendront.
  Marie will bring them bread and cheese when they come.

Yes, you can add chez elle:

• Marie leur apporte du pain et du fromage quand ils viennent chez elle.

In many contexts, quand ils viennent will naturally be understood as “when they come (to her place)”, so chez elle is often implied and not strictly necessary. Adding it just makes the location explicit.

Most likely yes:

• leur = to them (indirect object)
• ils = they (subject of viennent)

In context, it’s natural to understand that:

• They (ils) are the same people as them (leur):
  Marie brings bread and cheese to the people who come.

Grammatically, French doesn’t force them to be the same group, but in normal usage here they almost always are.

As an indirect object pronoun (the role it has here), leur is only plural and always means to them.

• lui = to him / to her (singular)
• leur = to them (plural)

Example:

• Marie lui apporte du pain. → Marie brings him/her bread.
• Marie leur apporte du pain. → Marie brings them bread.

Note: leur can also be a possessive adjective (leur maison = their house). In that other role it doesn’t show singular/plural for the owners, but that’s a different grammar point. In this sentence, it is clearly the pronoun (so plural).

The negation surrounds the verb (and stays together with the pronoun):

• Marie ne leur apporte pas de pain ni de fromage quand ils viennent.

Points to notice:

• ne comes before the pronoun+verb: ne leur apporte.
• pas comes after the verb: apporte pas.
• du pain / du fromage become de pain / de fromage after pas.
  (Partitive du → de in a negative sentence.)
• You can use ni… ni… (neither… nor…) to link the two nouns.