Guarda esa hoja en el archivador azul, que luego la necesitaremos para el seminario.

Guarda is the tú affirmative imperative of guardar.

So:

• guardar = to keep / to put away / to save
• guarda = put away / keep / store (addressing you, informal singular)

Compare:

• guardas = you keep / you store (present tense statement)
• guarda = keep / store! (command to tú)
• guarde = command for usted (formal singular)

So the sentence is giving an instruction to someone you address as tú.

Spanish demonstratives show distance from the speaker.

• esta hoja = this sheet, near me
• esa hoja = that sheet, near you / not right by me
• aquella hoja = that sheet over there, farther away

In this sentence, esa hoja suggests the sheet is not especially close to the speaker, or it is the one the listener is dealing with.

Also notice agreement:

• hoja is feminine singular
• so the demonstrative must also be feminine singular: esa

Yes. Hoja can mean both:

• leaf (of a tree)
• sheet (of paper)

The meaning depends on context. Here, because of archivador and seminario, it clearly means sheet of paper.

This is very common in Spanish: one word can cover meanings that English separates.

Archivador usually refers to something used to store or file documents. Depending on context, it could be translated as:

• file
• binder
• filing folder
• sometimes even filing cabinet or similar storage item

In this sentence, it sounds like a place where papers are kept, so file or binder works well.

The exact English word depends on the physical object being referred to.

El archivador azul agrees with archivador, not with hoja.

Here we have:

• hoja = feminine singular
• archivador = masculine singular

So:

• esa hoja
• el archivador azul

Each adjective or article matches the noun it belongs to.

Also, azul is one of those adjectives that often looks the same in masculine and feminine singular:

• el archivador azul
• la carpeta azul

Only the article changes there, not azul.

In Spanish, adjectives usually come after the noun, especially when they simply describe a factual quality like color, size, or shape.

So:

• archivador azul = blue file/binder
• coche rojo = red car
• casa grande = big house

That is the normal order in Spanish.

Because Spanish only has two mandatory contractions:

• a + el = al
• de + el = del

But:

• en + el stays en el

So en el archivador is completely normal.

Here que is not really functioning like a normal relative pronoun attached to archivador azul or hoja.

In this sentence, que introduces an explanation or justification:

• Guarda esa hoja en el archivador azul, que luego la necesitaremos...
• Put that sheet in the blue file, because we’ll need it later...

So this que is closer to because / since, especially in spoken or informal Spanish.

It is a very natural way to add a reason after a command.

Yes. You could say:

• Guarda esa hoja en el archivador azul porque luego la necesitaremos para el seminario.

That is very clear and standard.

Using just que after a comma is also common, especially in speech, and can sound a bit more immediate or conversational.

So both are possible, but the original phrasing has a natural spoken feel.

La refers back to esa hoja.

Because hoja is feminine singular, the direct object pronoun is la:

• esa hoja → la

So:

• la necesitaremos = we will need it

This avoids repeating la hoja again.

Compare:

• Necesitaremos la hoja.
• La necesitaremos.

Same meaning, but the second sounds less repetitive.

In Spanish, object pronouns usually go before a conjugated verb.

So:

• la necesitaremos = correct

With a fully conjugated future form like necesitaremos, you do not attach the pronoun to the end.

Pronouns can attach to the end only in certain cases, especially:

• infinitives: necesitarla
• gerunds: necesitándola
• affirmative commands: guárdala

So here:

• la necesitaremos = correct
• necesitaremosla = not correct

Necesitaremos is the first person plural future of necesitar:

• yo necesitaré = I will need
• tú necesitarás = you will need
• él/ella necesitará
• nosotros necesitaremos = we will need
• vosotros necesitaréis
• ellos necesitarán

So la necesitaremos means we will need it.

The subject nosotros is omitted because Spanish often leaves subject pronouns out when the verb ending already makes the subject clear.

Both are possible.

• la necesitaremos = we will need it
• la vamos a necesitar = we’re going to need it

In many contexts, both sound natural. The simple future can sound a bit more concise, while ir a + infinitive can feel a bit more immediate or conversational.

So the sentence uses a perfectly normal future tense, but another common option would also work.

Here luego means later.

So:

• que luego la necesitaremos = because we’ll need it later

Depending on context, luego can also mean then, but in this sentence later is the clearest meaning.

Adverbs like luego are often placed before the verb in Spanish.

So:

• luego la necesitaremos
• literally: later we will need it

This is a very normal word order.

You may also see adverbs in other positions depending on emphasis, but the original placement is natural and standard.

Because para expresses purpose or intended use here.

• para el seminario = for the seminar

It means the sheet will be needed as part of the seminar.

Very broadly:

• para often points to purpose, destination, use, goal
• por often points to cause, reason, exchange, movement through, duration, etc.

So para el seminario is the right choice.

Spanish often drops subject pronouns when the verb ending already shows who the subject is.

• necesitaremos already tells you the subject is nosotros
• so nosotros la necesitaremos is possible, but unnecessary unless you want emphasis

The version without nosotros sounds more natural in most contexts.

Yes, if it is already clear which sheet you mean.

• Guarda esa hoja en el archivador azul...
• Guárdala en el archivador azul...

Both are correct.

The second version uses the pronoun la attached to the affirmative command guarda:

• guarda + la = guárdala

Notice the written accent in guárdala. It is added to preserve the normal stress.

So the original sentence names the object explicitly, while guárdala would sound more compact once the object is already known.

Because azul does not normally change for gender in the singular.

So:

• el archivador azul
• la carpeta azul

But it does change for number:

• el archivador azul
• los archivadores azules
• la carpeta azul
• las carpetas azules

So the adjective stays the same in masculine/feminine singular, but adds -es in the plural.