לפני שהחברות באות, אני מנגבת את השולחן כדי שלא יהיו עליו פירורים.

לפני means before.

When Hebrew is followed by a noun, you can use just לפני:

• לפני הארוחה = before the meal

When it is followed by a whole clause, Hebrew usually uses לפני ש־:

• לפני שהחברות באות = before the friends come

So the ש־ here means something like that / when, and it introduces the clause.

Because ש־ is a prefix in Hebrew, not a separate word. It attaches directly to the next word.

So:

• ש + החברות → שהחברות

This is very common in Hebrew:

• אני יודע ש... = I know that...
• אחרי ש... = after...
• לפני ש... = before...

It can mean either one.

The singular חברה can mean:

• female friend
• company

So החברות can mean:

• the female friends
• the companies

Only context tells you which one is meant. In this sentence, if the meaning shown to the learner is about people coming over, then it means the female friends.

Because it agrees with החברות, which is grammatically feminine plural.

באות is the feminine plural present form of לבוא (to come).

Examples:

• החבר בא = the male friend comes
• החברה באה = the female friend comes
• החברים באים = the male/mixed friends come
• החברות באות = the female friends come

Yes, באות is formally a present-tense form.

In Hebrew, the present tense is often used for:

• habitual actions
• repeated situations
• near-future or context-based future meaning

Here the sentence sounds like a routine: Before the friends come, I wipe the table...

So the idea is probably whenever they come / when they’re coming over.

If you wanted a more clearly future-oriented version, you could also say:

• לפני שהחברות יבואו... = before the friends will come / before the friends come

Both are possible, but the nuance can be slightly different.

In this sentence, אני is very natural and usually needed.

The form מנגבת tells you:

• feminine
• singular
• present

But it does not tell you person clearly. מנגבת could mean:

• I wipe (spoken by a woman)
• you wipe (to one woman)
• she wipes

So Hebrew often includes the pronoun in the present tense when needed for clarity:

• אני מנגבת = I wipe
• את מנגבת = you wipe
• היא מנגבת = she wipes

Because the speaker is feminine.

Hebrew present-tense verb forms agree with the subject in gender and number. So:

• אני מנגב = I wipe (male speaker)
• אני מנגבת = I wipe (female speaker)

This tells you the speaker is a woman or girl.

את here is the marker of a definite direct object. It does not mean you in this sentence.

Since השולחן means the table and is definite because of ה־, Hebrew uses את before it:

• אני מנגבת את השולחן = I wipe the table

Compare:

• אני מנגבת שולחן = I wipe a table
• אני מנגבת את השולחן = I wipe the table

So את appears before definite direct objects.

כדי means in order to / so that, and שלא means that not / so that not.

Together, כדי שלא means:

• so that ... not
• in order that ... not

So:

• אני מנגבת את השולחן כדי שלא יהיו עליו פירורים means
• I wipe the table so that there won’t be crumbs on it

This is a very common way to express purpose negatively.

Because the speaker is talking about the result she wants after wiping.

She wipes the table now so that later there will not be crumbs on it. That is why Hebrew uses יהיו (will be).

Also, יהיו is plural because the subject is פירורים (crumbs), which is plural.

Compare:

• שלא יהיה פירור = so that there won’t be a crumb
• שלא יהיו פירורים = so that there won’t be crumbs

In the present tense, Hebrew often uses יש / אין for there is / there are:

• יש פירורים על השולחן = there are crumbs on the table
• אין פירורים על השולחן = there are no crumbs on the table

But for past and future, Hebrew uses forms of היה:

• היו פירורים = there were crumbs
• יהיו פירורים = there will be crumbs

So שלא יהיו עליו פירורים is the normal future-time structure.

עליו means on it or on him, depending on context.

It is made from:

• על = on
• ־יו = him/it (masculine singular suffix)

Here it refers to השולחן, which is masculine singular, so:

• עליו = on it

Similar forms:

• עליה = on her / on it (feminine singular)
• עליהם = on them (masculine/mixed plural)
• עליהן = on them (feminine plural)

Because Hebrew often uses a pronoun suffix to avoid repetition, just like English uses it.

So instead of saying:

• שלא יהיו על השולחן פירורים

the sentence says:

• שלא יהיו עליו פירורים

That sounds smoother and more natural because the table was already mentioned.

Because the meaning is any crumbs / crumbs in general, not specific crumbs already known to both speaker and listener.

So:

• פירורים = crumbs
• הפירורים = the crumbs

In this sentence, the speaker is not talking about a particular set of crumbs. She just wants there to be no crumbs at all.

Hebrew often places the verb before the noun in clauses like this, especially with there will be / there won’t be type meanings.

So:

• שלא יהיו עליו פירורים sounds natural

Literally, it is something like:

• that not will-be on-it crumbs

But in normal English, we translate it as:

• so that there won’t be crumbs on it

This kind of word order is very common in Hebrew existential sentences.

Yes. Hebrew often allows a few natural alternatives. For example:

• לפני שהחברות יבואו, אני מנגבת את השולחן כדי שלא יהיו עליו פירורים.

  • More clearly future-oriented

• לפני שהחברות באות, אני מנקה את השולחן כדי שלא יהיו עליו פירורים.

  • Using מנקה = clean instead of wipe

• ...כדי שלא יישארו עליו פירורים.

  • so that no crumbs remain on it

The original sentence is completely natural, but learners should know that Hebrew often has more than one good way to express the same idea.