אנחנו ממיינות את המלתחה לפני מסיבת ההחלפות.

Because the sentence is talking about we as an all-female group.

In Hebrew present tense, verbs agree with the subject in gender and number:

• ממיין = masculine singular
• ממיינת = feminine singular
• ממיינים = masculine plural / mixed-gender plural
• ממיינות = feminine plural

So אנחנו ממיינות means we (women / girls) are sorting.

If the group were mixed or all male, you would normally say אנחנו ממיינים.

In Hebrew present tense, the verb usually shows gender and number, but not person clearly enough by itself.

So ממיינות tells you:

• plural
• feminine

But it does not by itself clearly mean we rather than something like they in all contexts.

That is why Hebrew often includes the pronoun:

• אנחנו ממיינות = we are sorting
• הן ממיינות = they are sorting

The pronoun makes the subject explicit.

ממיינות comes from the verb למיין, which means to sort, to classify, or to organize by categories.

So in this sentence, ממיינות means:

• sorting
• organizing
• possibly going through and separating things into groups

It is the present tense feminine plural form of למיין.

Here את is the direct object marker. It does not mean you in this sentence.

Hebrew uses את before a definite direct object. Since המלתחה means the wardrobe / the closet, it is definite, so Hebrew uses את:

• ממיינות את המלתחה = sorting the wardrobe

Compare:

• אני קורא ספר = I’m reading a book
• אני קורא את הספר = I’m reading the book

So את marks המלתחה as the specific thing being sorted.

Because of the grammar and position in the sentence.

Hebrew את can mean two different things:

1. Direct object marker
2. You (feminine singular)

In אנחנו ממיינות את המלתחה, it must be the direct object marker, because it is followed by a noun:

• את המלתחה

If it meant you, the sentence structure would not make sense here.

המלתחה means the wardrobe, the closet, or sometimes the clothing storage area, depending on context.

It is made up of:

• מלתחה = wardrobe / closet
• ה־ = the

So:

• מלתחה = a wardrobe / closet
• המלתחה = the wardrobe / the closet

In context, it likely means they are sorting through clothes in a wardrobe or closet before the event.

לפני means before.

In this sentence:

• לפני מסיבת ההחלפות = before the swap party

It is used with a noun phrase to express time:

• לפני השיעור = before the lesson
• לפני הארוחה = before the meal

It can also mean in front of in other contexts, so learners often need to rely on context:

• time: before
• place: in front of

Here it clearly means before in time.

Because Hebrew often uses a construct chain (called סמיכות) instead of of.

So:

• מסיבת ההחלפות literally = party of the exchanges/swaps
• natural English = the swap party or the exchange party

In a construct chain:

• the first noun changes into a linked form
• the second noun carries the definiteness

Here:

• מסיבה = party
• מסיבת = party of ...
• ההחלפות = the swaps / the exchanges

Together:

• מסיבת ההחלפות = the swap party

This is usually more natural in Hebrew than saying המסיבה של...

That is how definiteness works in a Hebrew construct chain.

In מסיבת ההחלפות, the whole phrase is definite because the second noun is definite:

• ההחלפות = the swaps

So even though מסיבת does not have ה־, the full phrase is still understood as the swap party.

Compare:

• מסיבת החלפות = a swap party
• מסיבת ההחלפות = the swap party

This is very common in Hebrew.

Because החלפות is the plural of החלפה, which means exchange or swap.

A phrase like מסיבת החלפות or מסיבת ההחלפות refers to an event where people exchange multiple items, so the plural sounds natural:

• swap party
• literally, something like party of swaps/exchanges

Hebrew often uses the plural in event names of this kind.

It is present tense, but Hebrew present tense often covers both:

• We sort the wardrobe
• We are sorting the wardrobe

So אנחנו ממיינות את המלתחה can mean either one, depending on context.

If the context is an action happening right now, English would usually translate it as:

• We’re sorting the wardrobe

If it is more habitual, it could be:

• We sort the wardrobe

Yes. Hebrew present-tense forms historically behave a lot like participles, and they can sometimes function as adjectives or nouns in other contexts.

For example:

• נשים ממיינות could mean women are sorting or, in some contexts, sorting women depending on structure and context

But in אנחנו ממיינות את המלתחה, it is clearly functioning as the main verb:

• we are sorting the wardrobe

This dual nature is normal in Hebrew present-tense forms.

You would change ממיינות to ממיינים:

• אנחנו ממיינים את המלתחה לפני מסיבת ההחלפות.

That means:

• We (men / mixed group) are sorting the wardrobe before the swap party.

So the only change is the plural gender form of the verb:

• ממיינות = feminine plural
• ממיינים = masculine plural / mixed plural