Она забрала документы у администратора и сразу отдала их начальнице.

Because the subject is она (she), and both verbs are in the past tense feminine singular.

In Russian past tense, the verb agrees with the subject in gender and number:

• он забрал = he took
• она забрала = she took
• оно забрало = it took
• они забрали = they took

The same pattern applies to отдал / отдала / отдало / отдали.

So:

• Она забрала = she took / picked up
• Она отдала = she gave / handed over

Both can often be translated as took, but забрать usually has the idea of taking something away, picking it up, or collecting it from somewhere or someone.

So:

• взяла документы = took the documents
• забрала документы = took the documents away / picked up the documents

In this sentence, забрала fits well because she receives or collects the documents from the administrator and then passes them on.

Документы is the accusative plural form, because it is the direct object of both verbs: she picked up the documents and handed them over.

For many inanimate masculine plural nouns, the accusative plural looks the same as the nominative plural:

• документы = documents

So in this sentence:

• забрала что? → документы
• отдала что? → их (them, referring back to documents)

The phrase у + genitive is commonly used to mean from someone, especially when talking about taking, getting, borrowing, or receiving something from a person.

So:

• у администратора = from the administrator

The noun администратор changes to the genitive singular:

• nominative: администратор
• genitive: администратора

This construction is very common:

• взять у друга книгу = take a book from a friend
• забрать у секретаря папку = pick up a folder from the secretary

Because отдать usually takes:

• the thing given in the accusative
• the recipient in the dative

So in this sentence:

• отдала их = handed them over
• начальнице = to the boss / to the female supervisor

The noun начальница is feminine, and here it is in the dative singular:

• nominative: начальница
• dative: начальнице

Compare:

• отдать книгу брату = give the book to the brother
• отдать документы начальнице = give the documents to the female boss

Их means them and refers back to документы.

Russian often uses object pronouns just like English does to avoid repeating the noun:

• Она забрала документы у администратора и сразу отдала документы начальнице.
• This is grammatically possible, but sounds repetitive.

So the natural version is:

• ...и сразу отдала их начальнице.
• ...and immediately handed them to the boss.

Here их is the accusative plural form of the pronoun они.

Yes. For the pronoun они (they), the form их can be both:

• genitive = of them / from them
• accusative = them

In this sentence, it is accusative, because it is the direct object of отдала:

• отдала кого? что? → их

So even though the form looks the same, the function is clear from the sentence.

Сразу means immediately, right away, or at once.

It shows that the second action happened without delay:

• забрала документы = picked up the documents
• и сразу отдала их начальнице = and immediately handed them to the boss

It helps create a clear sequence: first she got the documents, then she passed them on right away.

Both забрала (from забрать) and отдала (from отдать) are perfective verbs. Perfective verbs present actions as completed whole events.

That fits this sentence because we are talking about two finished actions in sequence:

1. she picked up the documents
2. she handed them over

If imperfective forms were used, the meaning would be different or less natural in this context:

• забирала = was picking up / used to pick up
• отдавала = was handing over / used to hand over

Those would suggest process, repetition, or background action rather than two completed events.

Yes, Russian word order is flexible, but changing it can shift emphasis.

The given sentence is very natural:

• Она забрала документы у администратора и сразу отдала их начальнице.

Other possible versions:

• Она у администратора забрала документы и сразу отдала их начальнице.
• Документы она забрала у администратора и сразу отдала их начальнице.

These are still understandable, but the original is the most neutral. Russian often uses word order to highlight what is new, important, or contrasted.

Russian has no articles like English a/an and the.

So:

• документы can mean documents or the documents
• администратора can mean an administrator or the administrator
• начальнице can mean a boss or the boss

The exact meaning comes from context. In this sentence, English would probably use the:

• the documents
• the administrator
• the boss

But Russian does not need separate words for that.

Yes.

• начальник = a male boss / supervisor
• начальница = a female boss / supervisor

In your sentence, начальнице shows that the recipient is female.

This is a good example of how Russian often marks gender directly in nouns referring to people.

Then the past tense verbs would change to masculine:

• Он забрал документы у администратора и сразу отдал их начальнице.

Changes:

• забрала → забрал
• отдала → отдал

Everything else can stay the same if the rest of the meaning is unchanged.