المعازيم بيحتفلوا، والعريس لابس البدلة.

It is Egyptian Arabic.

A few clues:

• بيحتفلوا has the Egyptian present-tense marker بـ.
• المعازيم is a very common colloquial word for the invited guests.
• لابس is an active participle used in a very everyday spoken way to mean wearing.

A more formal MSA version would look different, for example with words like الضيوف يحتفلون and العريس يرتدي البدلة.

المعازيم means the invited guests or the invitees.

It is the plural of معزوم, which means invited. In context, it often refers to people invited to a wedding, party, feast, or celebration.

So compared with الضيوف:

• المعازيم = people who were invited
• الضيوف = guests in general

In a wedding sentence like this, المعازيم sounds very natural.

In Egyptian Arabic, بـ often marks the present tense.

So:

• يحتفلوا by itself is not the normal everyday present form here
• بيحتفلوا means they celebrate / they are celebrating

In this sentence, English translates it naturally as are celebrating because the action is happening now.

The ending ـوا shows that the subject is they.

So:

• بيحتفل = he celebrates / is celebrating
• بيحتفلوا = they celebrate / are celebrating

Since المعازيم is a plural human subject, the verb takes the plural ending ـوا.

Yes:

• بـ = present-tense marker in Egyptian Arabic
• يحتفل = celebrate
• ـوا = they ending

So بيحتفلوا literally works like they are celebrating.

In Arabic, the verb to be is usually not said in the present tense.

So instead of saying something like the groom is wearing the suit with a separate word for is, Egyptian Arabic simply says:

• العريس لابس البدلة

This is completely normal. The meaning is is understood automatically from the structure.

لابس means wearing in the sense of already having the clothes on.

That is why it fits this sentence well:

• العريس لابس البدلة = the groom is wearing the suit

By contrast, بيلبس usually means:

• he wears
• he is putting on
• sometimes he wears habitually

So the difference is often:

• لابس = in the state of wearing
• بيلبس = the action of putting on / wearing in general

Because they refer to specific, identifiable people or things in the situation:

• المعازيم = the guests
• العريس = the groom
• البدلة = the suit

This is very natural in Arabic. In a wedding context, these are not random nouns; they are the known guests, the known groom, and the suit he is wearing.

Yes, you can, but the nuance changes a little.

• الضيوف = the guests
• المعازيم = the invited guests

At a wedding or celebration, المعازيم often sounds more specific and culturally natural, because it emphasizes that these people were invited to the event.

Yes, but in connected speech they flow together.

والعريس is commonly pronounced something like wel-ʕarīs or wil-ʕarīs, depending on the speaker.

A useful thing to remember:

• و = and
• ال = the
• together they often sound like wel- or wil-

So you do not pause between them.

Yes, it is very normal in Egyptian Arabic.

This is a subject + verb pattern:

• المعازيم = the guests
• بيحتفلوا = are celebrating

In spoken Egyptian, subject-first word order is extremely common and natural.

A natural rough pronunciation is:

el-maʕāzīm biyiḥtaflu, wel-ʕarīs lābis el-badla

A few pronunciation notes:

• ع in المعازيم and العريس is a consonant that English does not have.
• ح in بيحتفلوا is a strong breathy h sound.
• ال in Egyptian is often pronounced el-.

So if you want a smooth spoken version, aim for:

el-maʕāzīm biyiḥtaflu, wel-ʕarīs lābis el-badla