Guarda bien el resguardo de la solicitud, porque te lo pueden pedir en la ventanilla.

Guarda is the affirmative tú imperative of guardar.

So Guarda bien el resguardo means Keep the receipt/slip safe or Make sure you keep the receipt well.

For -ar verbs, the tú affirmative command uses the él/ella/usted present form:

• guardar → guarda
• hablar → habla
• comprar → compra

This sentence is speaking directly to one person in an informal way.

If it were formal, it would be:

• Guarde bien el resguardo...

And if it were plural in Spain:

• Guardad bien el resguardo... (informal vosotros)
• Guarden bien el resguardo... (formal ustedes)

Here bien means something like carefully, properly, or safely.

So:

• Guarda el resguardo = Keep the receipt/slip.
• Guarda bien el resguardo = Keep it carefully / Make sure you keep it safe.

It adds the idea that this document is important and should not be lost.

In everyday Spanish, bien is often used this way to strengthen a verb:

• Míralo bien = Look at it carefully.
• Piénsalo bien = Think it through carefully.
• Guárdalo bien = Keep it somewhere safe.

In this context, resguardo usually means a receipt, proof of submission, acknowledgement slip, or document showing that you filed something.

Because the sentence also says de la solicitud and mentions la ventanilla, this is probably about an official administrative process. So el resguardo de la solicitud is likely the paper or document that proves you submitted the application.

This is not exactly the same as a shop receipt in every context. It often has the sense of proof that something was deposited, handed in, or registered.

De la solicitud means of the application or for the application.

It tells you which resguardo we are talking about:

• el resguardo = the receipt / proof slip
• de la solicitud = for the application / of the application

So the whole phrase means:

• the receipt/proof slip for the application

This is a very common Spanish structure:

• el número de teléfono = the phone number
• la fecha de nacimiento = date of birth
• el justificante de pago = proof of payment

English often uses of less naturally here and prefers something like application receipt or receipt for the application, but Spanish commonly uses de.

The comma separates the main instruction from the explanation:

• Guarda bien el resguardo de la solicitud,
• porque te lo pueden pedir en la ventanilla.

So the structure is:

• command: Keep the application receipt safe
• reason: because they may ask you for it at the counter/window

In Spanish, a comma before porque is common when the second part explains the first, especially in longer sentences. You may also see sentences without the comma in other contexts, but here the pause sounds natural and clear.

It breaks down like this:

• te = to you / from you
• lo = it
• pueden = they can / they may
• pedir = ask for

So literally it is something like:

• They can ask it from you

More natural English:

• They may ask you for it
• They might ask to see it
• You may be asked for it

The pronouns work like this:

• pedir algo a alguien = to ask someone for something

Example:

• Te piden el resguardo = They ask you for the receipt.

When replacing el resguardo with a pronoun, it becomes lo:

• Te lo piden = They ask you for it.

And with pueden:

• Te lo pueden pedir = They may ask you for it.

Because the verb pedir can involve both:

• the person affected: te = you
• the thing being asked for: lo = it

Spanish often uses both pronouns together.

Order matters. With unstressed pronouns, indirect-object pronouns usually come before direct-object pronouns:

• me lo
• te lo
• se lo
• nos lo
• os lo
• se lo

So:

• te lo pueden pedir = they may ask you for it

You cannot say lo te pueden pedir.

A useful comparison:

• Te pueden pedir el resguardo = They may ask you for the receipt.
• Te lo pueden pedir = They may ask you for it.

Yes. Lo refers to el resguardo.

Since resguardo is:

• singular
• masculine

the direct-object pronoun is:

• lo

Compare:

• el resguardo → lo
• la solicitud → la
• los documentos → los
• las copias → las

So:

• Te pueden pedir el resguardo → Te lo pueden pedir

If the sentence were about la solicitud, it would be:

• Te la pueden pedir = They may ask you for it.

Pueden is third person plural: they can / they may.

But in Spanish, this form is often used generically when the specific people are not important or not known. Here it means something like:

• they = the staff, the officials, the clerks, the people at the office

This is very natural in both Spanish and English:

• Aquí te piden el DNI = Here they ask you for your ID.
• En esta oficina no te atienden sin cita = At this office they don’t help you without an appointment.

So pueden does not necessarily point to a clearly identified group. It just means that at some point, the people working there may ask for that document.

Literally, ventanilla does come from ventana and originally means a small window.

But in Spain, in office and administrative contexts, la ventanilla commonly means:

• the service window
• the counter
• the desk/window where the clerk serves you

So in this sentence:

• en la ventanilla = at the service window / at the counter

This is very common in public administration, banks, post offices, town halls, transport offices, etc.

It does not usually mean a physical window in the ordinary everyday sense here.

Because en here indicates the place or point of service where something happens:

• te lo pueden pedir en la ventanilla = they may ask you for it at the counter/window

It answers where?

By contrast, a la ventanilla would more naturally suggest movement toward the window/counter:

• Ve a la ventanilla 3 = Go to window 3.

So:

• en la ventanilla = at the counter / there, in that service point
• a la ventanilla = to the counter / toward that place

Yes. Te lo pueden pedir and pueden pedírtelo mean the same thing.

Both are correct because with an infinitive like pedir, the attached pronouns can go either:

• before the conjugated verb: te lo pueden pedir
• attached to the infinitive: pueden pedírtelo

So these are equivalent:

• Te lo pueden pedir
• Pueden pedírtelo

The first version is often a bit easier for learners to process because the pronouns appear earlier. The second is also completely natural.

Notice the written accent in pedírtelo. It is needed because adding pronouns changes the stress pattern.

Solicitud often means application in administrative contexts, but more broadly it means request.

So depending on the situation, it could be:

• an application form
• a formal request
• a submitted request for some service, permit, benefit, etc.

In this sentence, because of resguardo and ventanilla, it strongly sounds like an official application or request filed with an office.

Yes, it sounds very natural for Spain, especially because of the administrative-office vocabulary.

A few especially Spain-flavored elements are:

• la ventanilla in the sense of an administrative service window
• the overall bureaucratic style
• the use of tú in an instruction to one person

The sentence would still be understood in many Spanish-speaking places, but the exact feel is very typical of public-office Spanish in Spain.