Bien que Marie aime le saumon, elle est obligée de cuisiner du thon pour sa cousine.

Bien que means although or even though.

It introduces a contrast:

• Bien que Marie aime le saumon = Although Marie likes salmon
• elle est obligée de cuisiner du thon = she has to cook tuna

A learner might notice that bien usually means well and que often means that, but together bien que is a fixed expression meaning although.

After bien que, French normally uses the subjunctive mood.

So in this sentence, aime is the subjunctive present of aimer.

That can be confusing because for many -er verbs, the je / tu / il / elle / on forms of the present subjunctive look exactly the same as the regular present indicative:

• indicative: elle aime
• subjunctive: qu’elle aime

So the form looks the same, but the grammar is different. The trigger here is bien que, which requires the subjunctive.

This is a very common question because French uses articles differently depending on meaning.

• le saumon here refers to salmon in a general sense: Marie likes salmon.
• du thon is a partitive article, meaning some tuna or tuna as food being prepared.

So:

• aimer + definite article is common for likes and dislikes:
  • J’aime le café = I like coffee
• with food you are cooking, eating, buying, etc., French often uses the partitive:
  • cuisiner du thon = cook some tuna / cook tuna

So the difference is not about the fish themselves, but about how they are being talked about.

Du is the partitive article for masculine singular nouns.

It comes from de + le = du.

French uses the partitive article for an unspecified amount of something, especially with food, drink, or uncountable items:

• du pain = some bread
• du fromage = some cheese
• du thon = some tuna

So cuisiner du thon means she is cooking tuna, not necessarily one whole tuna fish.

Because Marie is female, the adjective must agree with her.

• masculine: obligé
• feminine: obligée

So:

• il est obligé = he is obliged / forced / required
• elle est obligée = she is obliged / forced / required

The extra -e marks the feminine form in writing. In pronunciation, the difference may or may not be clearly heard depending on the word, but in writing the agreement is required.

This is a standard French structure:

• être obligé de faire quelque chose = to be obliged / forced / required to do something

So:

• elle est obligée de cuisiner = she is obliged to cook

You cannot say elle est obligée cuisiner without de. The de is part of the construction.

Similar examples:

• Je suis obligé de partir. = I have to leave.
• Nous sommes obligés d’attendre. = We have to wait.

Yes, but the nuance is a little different.

• elle doit cuisiner du thon = she must / has to cook tuna
• elle est obligée de cuisiner du thon = she is obliged / forced / has no choice but to cook tuna

Est obligée de often sounds a bit stronger, as if circumstances are forcing her to do it.

So both can work, but est obligée de emphasizes the constraint more clearly.

Here pour means for in the sense of for the benefit of someone.

• cuisiner du thon pour sa cousine = cook tuna for her cousin

If you used à sa cousine, it would sound more like the tuna is being given or directed to the cousin, not that the cooking is being done for her benefit. With cuisiner, pour is the natural choice here.

Compare:

• Je cuisine pour ma famille. = I cook for my family.
• Je donne le plat à ma cousine. = I give the dish to my cousin.

In French, possessive adjectives agree with the thing possessed, not with the owner.

The noun cousine is feminine singular, so French uses sa:

• sa cousine = his/her cousin (female cousin)

It does not matter that Marie is female. What matters for sa is that cousine is feminine.

Compare:

• son cousin = his/her male cousin
• sa cousine = his/her female cousin

Yes.

French distinguishes between male and female cousins:

• un cousin = a male cousin
• une cousine = a female cousin

English uses cousin for both, but French makes the gender explicit.

So sa cousine clearly means her female cousin.

A careful pronunciation would be approximately:

byen kuh ma-REE em luh soh-MON, el eh zob-lee-ZHAY duh kwee-zee-NAY dyu TON poor sa koo-ZEEN

A few useful pronunciation notes:

• Bien que: the n in bien is nasal, and que is pronounced roughly like kuh
• Marie aime: in natural speech, this often flows together smoothly
• est obligée: the t in est links to the following vowel, so you often hear eh zobligée
• thon has a nasal vowel; the n is not pronounced like an English n
• cousine ends with a voiced z sound: koo-zeen

The structure is:

• Bien que + clause
• main clause

So:

• Bien que Marie aime le saumon
  = subordinate clause introduced by bien que
• elle est obligée de cuisiner du thon pour sa cousine
  = main clause

This is very similar to English:

• Although Marie likes salmon, she has to cook tuna for her cousin.

French punctuation and word order here are straightforward, even if the subjunctive and article choices are more advanced.