Learn Hardcore French: Je n’ai vu personne au musée hier soir. - I didn’t see anyone at the museum last night.

Because French has several negative pairs where the second element replaces "pas." Here it’s ne … personne (not … anyone/nobody). So you say Je n’ai vu personne, not with "pas." Other pairs include ne … rien (nothing), ne … jamais (never), ne … plus (no longer).

Where does "personne" go in a compound tense like this?

As a direct object in compound tenses, it goes after the past participle: Je n’ai vu personne.
If there’s a preposition required by the verb, keep it: Je n’ai parlé à personne. / Je n’ai besoin de personne.
If "personne" is the subject, it goes before the verb with ne after it: Personne n’a vu…

Is this a double negative?

Not in French. It’s normal "negative concord": ne pairs with a negative word (personne, rien, etc.). So Je n’ai vu personne is correct and standard.

Can I drop "ne" when speaking?

Yes, in informal speech many speakers drop "ne": J’ai vu personne au musée hier soir. Keep ne in careful speech and writing.

What is "vu," and why is "ai" used?

vu is the past participle of voir (to see).
ai is the present tense of avoir, the auxiliary used to form the passé composé. So je n’ai vu = "I have/ did see" in English past.

Does "vu" have to agree in gender or number here?

No. With avoir, the past participle agrees only if the direct object comes before it. Here, personne comes after vu, so no agreement: vu.

Example with agreement: Les personnes que j’ai vues (direct object "les personnes" is before the participle via "que").

What if "personne" is the subject instead of the object?

Use Personne ne + verb:

Personne n’a vu le tableau. (Nobody saw the painting.)
If you say "Nobody saw me," you also get participle agreement with a preceding object pronoun:
- If the speaker is male: Personne ne m’a vu.
- If the speaker is female: Personne ne m’a vue.

What’s the difference between "personne" and "rien"?

personne = nobody / no one (people)
- Je n’ai vu personne.
rien = nothing (things)
- Je n’ai rien vu. They’re not interchangeable.

Why "au musée" instead of "à le musée"?

Because à + le contracts to au. Similarly, à + les = aux; but à la and à l’ do not contract.

Is there a difference between "au musée" and "dans le musée"?

au musée = at the museum (general location; the normal choice)
dans le musée = inside the museum (emphasizes being physically inside)

Can "hier soir" move around in the sentence?

Yes. Common options:

Je n’ai vu personne au musée hier soir.
Hier soir, je n’ai vu personne au musée. Both are natural. French tends to place general time expressions at the end or the beginning.

Is "hier soir" the same as "la nuit dernière"?

Not exactly:

hier soir = last evening
la nuit dernière = last night (during the night) Use whichever matches the time you mean.

How do I say "someone/anyone" in this context?

Affirmative: quelqu’un — J’ai vu quelqu’un au musée.
Questions: Tu as vu quelqu’un au musée ? / Est-ce que tu as vu quelqu’un… ?
Negative: personne — Je n’ai vu personne.

Do I ever need "de" before "personne"?

Only if the verb requires de:

J’ai besoin de quelqu’un → Je n’ai besoin de personne.
Je parle de quelqu’un → Je ne parle de personne.
With verbs that take a direct object (like voir), no preposition: Je n’ai vu personne.

Is "Je n’ai pas vu personne" ever correct?

Not in standard French. Use Je n’ai vu personne. (Some regional or very informal varieties may add "pas," but avoid this in standard usage.)

Why is there an apostrophe in "n’ai"?

ne elides to n’ before a vowel or mute h to ease pronunciation: ne ai → n’ai.

Any tips on pronouncing the sentence naturally?

Liaison: link the n’ to ai in n’ai ([n‿e]).
Approximate sounds:
- Je n’ai: zhuh nay
- vu: voo
- personne: pehr-son
- au musée: oh myu-zay
- hier: yair (also ee-yair is heard)
- soir: swar
  Say it smoothly: "Zhuh nay voo pehr-son oh myu-zay yair swar."