L’étiquette de retour accompagne la preuve d’achat.

Because French uses elision: la becomes l’ before a word that begins with a vowel sound.

• la étiquette → l’étiquette
• This is very common in French:
  • l’école
  • l’amie
  • l’idée

Since étiquette is feminine singular, the full article is la, but it shortens to l’ here.

Yes, étiquette is a feminine noun.

In this sentence, you can tell because the article is underlyingly la, which becomes l’ before the vowel:

• la étiquette → l’étiquette

You often have to memorize noun gender in French, but endings like -ette are very often feminine, so étiquette fits a common pattern.

Here, de retour means something like for return or return-related.

So une étiquette de retour is a return label.

This is a very common French structure:

• nom + de + nom

Examples:

• ticket de bus = bus ticket
• carte de visite = business card
• étiquette de retour = return label

It does not mean the label is itself returning. It means it is a label used for a return.

Both are possible in French, but they mean slightly different things.

In your sentence, preuve d’achat is the standard fixed expression for proof of purchase. It is a general administrative phrase.

• preuve d’achat = proof of purchase, purchase evidence in general

If you say preuve de l’achat, that sounds more like proof of the purchase, meaning a specific purchase already identified in context.

Also, de becomes d’ before a vowel sound:

• de achat → d’achat

So:

• la preuve d’achat = the normal expression
• la preuve de l’achat = more specific, less formulaic here

Because in many French expressions, de + noun is used without an article when the noun expresses a general category or function.

That is what happens in:

• preuve d’achat
• carte d’identité
• salle de bain
• verre d’eau

So achat here is not being presented as the purchase in a specific sense. It is part of a set phrase meaning proof of purchase.

Accompagne is the third-person singular present tense of accompagner.

The subject is L’étiquette de retour, which is singular, so the verb is singular too:

• j’accompagne
• tu accompagnes
• il / elle accompagne

So in this sentence:

• L’étiquette de retour accompagne... = the return label accompanies...

It literally means accompanies, but in this kind of formal or administrative sentence, English might often use:

• comes with
• is included with
• is enclosed with

So accompagner is being used in a fairly formal, practical way here. It does not have to imply a person physically escorting something; it can simply mean one document or item goes together with another.

French generally uses articles more often than English does.

So where English might say something like:

• Return label accompanies proof of purchase

French normally wants the articles:

• L’étiquette de retour accompagne la preuve d’achat.

Even in formal or instructional language, French usually keeps the article unless there is a specific reason not to.

A reasonable pronunciation guide is:

L’étiquette de retour accompagne la preuve d’achat
Approximate English-style pronunciation: lay-tee-ket duh ruh-toor ah-kohn-pahn(y) la pruhv dah-sha

A few useful notes:

• L’étiquette sounds like lay-tee-ket
• retour has a French r
• accompagne ends with the gn sound, like ny in canyon
• achat ends with sha

A more IPA-style version is:

/letikɛt də ʁətuʁ akɔ̃paɲ la pʁœv daʃa/

Not exactly.

Preuve d’achat is broader than receipt. It means any document or evidence showing that the purchase was made.

It could be:

• a receipt
• an invoice
• an order confirmation
• another valid purchase record

So preuve d’achat is often best understood as a general administrative term, while receipt is just one possible type of proof.

Not normally, if you want to keep the same neutral statement.

French here uses the standard order:

• subject + verb + object

So:

• L’étiquette de retour = subject
• accompagne = verb
• la preuve d’achat = object

Changing the order would either sound unnatural or would require a different structure entirely. As written, this is the normal and straightforward French sentence pattern.