Mi compañera me pidió dos grapas porque la grapadora estaba vacía.

Me is an indirect object pronoun and means to me.

So:

• pidió = asked for / requested
• me pidió = asked me for

In fuller form, the idea is:

• Mi compañera me pidió dos grapas = My female colleague/classmate asked me for two staples

Spanish usually uses these little object pronouns where English often uses a separate phrase like to me, for me, him, her, etc.

Other examples:

• Me pidió ayuda. = She asked me for help.
• Le pidió ayuda a Ana. = He/She asked Ana for help.

Pidió is the preterite form of pedir, used for a completed action in the past.

• pidió = she asked / she requested
• pedía = she was asking / she used to ask

In this sentence, the speaker is talking about one specific completed event, so pidió fits best.

Compare:

• Mi compañera me pidió dos grapas = one completed request
• Mi compañera me pedía grapas todos los días = she used to ask me for staples every day / she was asking me for staples

Also note that pedir is a stem-changing verb in some forms, but in the preterite él/ella/usted form it becomes pidió.

Estaba is the imperfect of estar, and here it describes a background state or condition: the stapler was empty.

That is exactly the kind of thing the imperfect is often used for:

• background information
• description
• ongoing states
• the reason or situation around another action

So the structure is:

• main event: me pidió dos grapas
• background reason: porque la grapadora estaba vacía

Using estuvo vacía would sound more like focusing on the stapler being empty as a completed event or bounded state, which is not the natural choice here.

A very common pattern is:

• [preterite action] porque [imperfect description/state]

For example:

• Llegué tarde porque el autobús iba lleno.
• No pude imprimir porque la impresora estaba rota.

Because vacía agrees with la grapadora, which is a feminine singular noun.

Agreement in Spanish means adjectives change form to match the noun:

• la grapadora vacía
• el cajón vacío
• las cajas vacías
• los cajones vacíos

So here:

• grapadora = feminine singular
• therefore vacía = feminine singular

Compañera is the feminine form of compañero, and it can mean several things depending on context:

• colleague / coworker
• classmate
• teammate
• sometimes just companion

It does not automatically mean friend. It often refers to someone you share a workplace, class, or activity with.

Because the sentence says mi compañera, the speaker is referring to a woman in that kind of shared context.

Because compañera and amiga are not the same.

• amiga = female friend
• compañera = female colleague/classmate/teammate/associate

A person can be both, but the words emphasize different relationships.

If the speaker says mi compañera, the focus is probably on the shared setting, not on friendship.

In Spain, compañero/a is very common and natural in everyday speech.

This is a very common learner question.

• pedir = to ask for, to request
• preguntar = to ask a question

In this sentence, the person wanted two staples, so Spanish uses pedir.

Examples:

• Me pidió dos grapas. = She asked me for two staples.
• Me preguntó dónde estaba la grapadora. = She asked me where the stapler was.

A useful rule:

• if you ask for a thing, use pedir
• if you ask a question, use preguntar

Yes. In this context, grapa means staple.

So:

• dos grapas = two staples
• la grapadora = the stapler

These two words are closely related:

• grapa = staple
• grapadora = stapler

That makes the sentence very logical: she asked for staples because the stapler was empty.

Yes, grapadora is the standard and very natural word in Spain for stapler.

You may also hear regional variation in other Spanish-speaking countries, but for Spanish from Spain, grapadora is exactly what a learner should know.

So this sentence sounds natural for Spain.

Here, la is just the normal definite article: the.

• la grapadora = the stapler

Spanish uses articles very frequently, often more consistently than English. In this sentence, the article is completely natural and expected.

Could you omit it? No, not in this structure:

• porque grapadora estaba vacía ❌

You need the noun phrase:

• porque la grapadora estaba vacía ✅

Yes. That would also be natural.

Compare:

• porque la grapadora estaba vacía = because the stapler was empty
• porque no tenía grapas = because it didn’t have staples

Both work well. The original sentence sounds perfectly natural and slightly more descriptive.

In everyday Spanish, you might hear either one.

Yes. You can change the order:

• Mi compañera me pidió dos grapas porque la grapadora estaba vacía.
• Porque la grapadora estaba vacía, mi compañera me pidió dos grapas.

Both are grammatical.

The original version sounds more neutral and natural in ordinary conversation. Starting with porque puts more emphasis on the reason.

Before a noun, Spanish uses the short possessive form:

• mi = my
• tu = your
• su = his/her/your/their

These forms do not change for masculine or feminine singular nouns:

• mi compañero
• mi compañera

So mi works with both.

The longer forms like mío, mía, míos, mías are used differently, usually not directly before the noun in this kind of sentence:

• La compañera es mía. = The colleague/classmate is mine.

So here, mi compañera is exactly right.

Yes, very natural.

Everything in it sounds standard and idiomatic for Spain:

• mi compañera
• me pidió
• dos grapas
• la grapadora
• estaba vacía

It sounds like a normal real-life office or classroom sentence.