Pouvez-vous me dire si le musée est ouvert en août, madame?

This is the standard inversion pattern for a formal yes/no question in French.

• Statement: Vous pouvez me dire... = You can tell me...
• Question: Pouvez-vous me dire... ? = Can you tell me... ?

French often forms formal questions by switching the verb and subject pronoun and joining them with a hyphen:

• Vous pouvez → Pouvez-vous
• Il est → Est-il

This sounds polite and fairly formal, which fits the use of madame.

In French, when a question is formed by inversion, the verb and subject pronoun are linked with a hyphen.

So:

• pouvez
  • vous → Pouvez-vous

This is a spelling rule for inverted questions, not an optional stylistic choice.

French object pronouns like me, te, lui, nous, vous, leur usually come before the infinitive when the infinitive depends on another verb.

So:

• Pouvez-vous me dire... = Can you tell me...

Compare:

• Je veux te parler = I want to speak to you
• Elle va nous aider = She is going to help us

English often puts the object after the verb, but French pronouns often come before it.

Yes, here si means whether or if in an indirect yes/no question.

• Pouvez-vous me dire si le musée est ouvert... ?
• Can you tell me whether the museum is open...?

This is different from si meaning if in a conditional sentence, although English uses the same word for both.

Important distinction:

• si = whether/if after verbs like dire, savoir, demander
• Example: Je ne sais pas si c’est vrai. = I don’t know whether it’s true.

French usually needs an article where English often does not.

So French says:

• le musée = the museum

Even when English might say something like Is museum open? in very informal shorthand, standard French still normally needs the article.

Common examples:

• la banque
• le restaurant
• l’école

Here ouvert is an adjective meaning open, and est is the verb to be.

So:

• le musée est ouvert = the museum is open

French often expresses this idea with être + adjective, just like English.

Compare:

• Le magasin est fermé. = The shop is closed.
• La bibliothèque est ouverte. = The library is open.

Also note agreement:

• ouvert is masculine singular because musée is masculine singular.
• If it were la bibliothèque, you would say ouverte.

French normally uses en with months.

• en août = in August
• en janvier = in January
• en été = in summer

So en is the usual preposition here.

The circumflex in août is part of the standard spelling of the word.

• août = August

Historically, circumflex accents often reflect older spellings or sound changes in French. For a learner, the main thing is simply to memorize the word as août.

In modern writing, this accent is still normally kept.

août is pronounced roughly like oot in many modern accents, though pronunciation can vary a little.

A simple learner-friendly approximation is:

• août ≈ oot

The final t is usually silent.

Here vous is most likely singular polite.

French uses:

• tu for one person in informal situations
• vous for:
  • one person formally/politely
  • more than one person

Since the sentence ends with madame, it is clearly addressing one woman politely, so vous is singular formal here.

French often puts words like madame, monsieur, or someone’s name at the end of a question or request for politeness or direct address.

• Pouvez-vous me dire..., madame ?

This is similar to English:

• Can you tell me..., ma’am?

It helps make the sentence sound courteous and respectful.

In ordinary French sentences, madame is usually lowercase unless it starts the sentence.

So:

• ..., madame ? is normal
• Madame, pouvez-vous... ? would be capitalized because it begins the sentence

This is a normal capitalization rule, not a sign of less respect.

Yes. A few common alternatives are:

• Vous pouvez me dire si le musée est ouvert en août ?

  • Still polite, but less formal than inversion

• Est-ce que vous pouvez me dire si le musée est ouvert en août ?

  • Very common spoken French

• Tu peux me dire si le musée est ouvert en août ?

  • Informal; only appropriate with someone you know well or in a casual context

The original sentence, Pouvez-vous me dire..., is especially polite and suitable for speaking to a stranger.

No, not in this sentence.

Use si for an indirect yes/no question:

• Pouvez-vous me dire si le musée est ouvert... ?

Use ce que / que for an indirect question about information that is not yes/no:

• Pouvez-vous me dire ce que vous cherchez ?
• Can you tell me what you are looking for?

So here, because the hidden question is basically Is the museum open in August?, si is the correct word.