אם את לא צריכה את הספר, תחזירי לי אותו מחר.

No. These are two different words that just happen to be spelled the same:

• את in אם את לא צריכה = you (feminine singular)
• את in את הספר = the direct object marker

So:

• אם את לא צריכה = if you don’t need
• את הספר = the book as a definite direct object

This is a very common source of confusion for learners.

Because the sentence is addressed to a female.

In Hebrew, verbs and adjectives often agree with the person’s gender. Here, צריכה is the feminine singular form of need.

Compare:

• to a woman: את לא צריכה
• to a man: אתה לא צריך

So this sentence is specifically being said to one female person.

For the same reason: the speaker is talking to one female person.

תחזירי is the future, feminine singular form of להחזיר (to return / give back).

Compare:

• to a woman: תחזירי
• to a man: תחזיר

Hebrew keeps this gender agreement consistently across the sentence.

In modern Hebrew, the future tense is often used to give commands, requests, or instructions, especially in everyday speech.

So תחזירי לי אותו מחר literally looks like you will return it to me tomorrow, but in context it means:

• return it to me tomorrow
• please bring it back to me tomorrow

This is very natural in spoken Hebrew. The true imperative exists, but future forms are often more common in everyday use.

הספר means the book. Since it is a definite direct object (the book, not just a book), Hebrew usually puts את before it.

So:

• ספר = a book / book
• את הספר = the book as the direct object of the verb

Hebrew uses את before definite direct objects, but it usually does not get translated into English.

לי means to me.

It is made from:

• ל־ = to
• ־י = me

So תחזירי לי אותו means return it to me or give it back to me.

אותו means it or him, depending on context. Here it means it, referring to הספר (the book).

It is masculine because ספר is a masculine noun. In Hebrew, object pronouns agree with the noun they refer to.

So:

• הספר = masculine singular
• therefore: אותו = it (masculine singular)

If the noun were feminine, you would use אותה.

Yes, it does repeat it, and that is normal in Hebrew.

The sentence first mentions the noun explicitly:

• את הספר = the book

Then later it refers back to it with a pronoun:

• אותו = it

This is similar to English sentences like:

• If you don’t need the book, return it to me tomorrow.

English also uses both the book and later it, so the Hebrew structure is very natural.

It behaves more like an adjective or predicate form meaning in need of / needing, rather than a simple standalone verb like English need.

That is why it changes for gender and number:

• צריך — masculine singular
• צריכה — feminine singular
• צריכים — masculine plural
• צריכות — feminine plural

So את לא צריכה את הספר is literally closer to you are not needing the book, but in natural English we say you don’t need the book.

אם means if.

It introduces a condition:

• אם את לא צריכה את הספר = If you don’t need the book

Then the second part gives the result or instruction:

• תחזירי לי אותו מחר = return it to me tomorrow

So the whole sentence has a standard if + result/request structure.

The word order here is very natural, but Hebrew word order is somewhat flexible.

This sentence follows a common pattern:

• אם
  • subject + negation + predicate + object,
• then the main clause with verb + indirect object + direct object pronoun + time expression

So:

• אם את לא צריכה את הספר, תחזירי לי אותו מחר.

You might move מחר earlier for emphasis, but the given version sounds very normal and neutral.

Usually no, not in this sentence.

After תחזירי לי you need to say what should be returned. אותו supplies that information: it.

So:

• תחזירי לי אותו = return it to me
• תחזירי לי by itself sounds incomplete unless the object is understood very clearly from context

In most cases, keeping אותו is the natural choice.

You would change the forms to masculine singular:

• אם אתה לא צריך את הספר, תחזיר לי אותו מחר.

Changes:

• את → אתה
• צריכה → צריך
• תחזירי → תחזיר

Everything else stays the same.

You would use plural forms.

To a group of men or a mixed group:

• אם אתם לא צריכים את הספר, תחזירו לי אותו מחר.

To a group of women:

• אם אתן לא צריכות את הספר, תחזירו לי אותו מחר.

Notice:

• אתם / אתן = you plural
• צריכים / צריכות = plural agreement
• תחזירו = plural you will return / return!

The dictionary form is להחזיר, which means to return, to give back, or sometimes to bring back.

So the forms are related like this:

• להחזיר = to return
• תחזירי = you (feminine singular) will return / return!

This verb is very common in everyday Hebrew, especially for returning borrowed things.