Learn Hardcore Swahili: Wageni watapiga makofi bi harusi na bwana harusi watakapoingia. - Guests will clap when the bride and groom enter.

Main clause: Wageni watapiga makofi = The guests will clap.
“When” clause: bi harusi na bwana harusi watakapoingia = when the bride and groom enter. So the sentence means: The guests will clap when the bride and groom enter.

How do we know that watakapoingia (“when they (will) enter”) refers to the bride and groom, not the guests?

Because the “when” clause immediately follows bi harusi na bwana harusi. In Swahili, a relative/temporal clause typically attaches to the nearest appropriate noun phrase. Also, semantically it makes sense: people clap when the couple enters. You could also front the “when” clause to make it crystal clear: Bi harusi na bwana harusi watakapoingia, wageni watapiga makofi.

What does the verb form watakapoingia consist of?

It’s built from several pieces:

wa- = they (class 2/human plural subject marker)
-ta- = future tense
-ka- = linker used in temporal/relative constructions
-po = locative/temporal relative marker “when/at the time”
ingia = enter Together: wa-ta-ka-po-ingia = “when they (will) enter.”

Why is it future in both clauses? English often says “will clap when they enter” (present in the when-clause), but Swahili has watakapoingia with -ta-.

Swahili commonly keeps future marking in the “when” clause for future events: watakapoingia literally “when they will enter.” It’s normal and idiomatic. You could also use wakiingia for a more general “when/whenever/as they enter” sense, but with a scheduled future event, -takapo- is a good fit.

What’s the literal meaning of piga makofi? Why piga?

piga literally means “to hit/strike.”
kofi/makofi is “a slap/clap” (singular/plural). So piga makofi is “to hit claps,” i.e., to clap (applaud). Swahili uses piga in many set phrases: piga simu (make a call), piga picha (take a photo), piga kelele (make noise).

Does piga makofi take a direct object like “clap someone”?

No. It’s typically intransitive: “to clap.” If you want to be explicit that you clap for someone, use the applied form pigia:

Wageni watawapigia makofi bi harusi na bwana harusi = The guests will clap for the bride and groom.
Here -wa- is the object marker “them” (the couple), and -pigia means “clap for.”

Is the punctuation correct without a comma before the when-clause?

Yes. A comma is optional in Swahili here. You may insert one for readability:
Wageni watapiga makofi, bi harusi na bwana harusi watakapoingia.
Both are acceptable.

Why is it wageni (plural) and watapiga with wa-?

mgeni = guest (class 1), wageni = guests (class 2). Verbs agree with the subject’s noun class and number: wa- is the class 2 plural subject prefix, so watapiga = “they will clap.”

Why does watakapoingia also begin with wa- if the subjects there are the bride and groom?

Because “bride and groom” together are plural humans, so they also take the class 2 plural subject marker wa-. Hence watakapo-.

What do bi harusi and bwana harusi mean exactly?

bi harusi = the bride (bi is a respectful female title that’s fossilized here; many also write Bi harusi, capitalized)
bwana harusi = the groom (bwana is “Mr./sir/man,” also fossilized in this compound; often Bwana harusi)

Can I say bibi harusi instead of bi harusi?

You will hear bibi harusi in some areas, but note that bibi on its own often means “grandmother/older woman.” The standard wedding term is Bi harusi (or lowercase bi harusi) for “bride.”

Is the order bi harusi na bwana harusi fixed? Could I say bwana harusi na bi harusi?

Either order is fine. Both are natural. English often says “bride and groom,” and Swahili usage varies.

Could I replace the whole “bride and groom” phrase with a single word?

Yes, you can say maharusi to refer to the couple (the newlyweds/bride-and-groom as a pair):
Wageni watapiga makofi maharusi watakapoingia.

What’s the difference between watakapoingia and walipoingia?

watakapoingia = when they (will) enter (future time)
walipoingia = when they entered (past time)
Same structure, different tense marker (-ta- future vs -li- past).

Is watapoingia (without the ka) acceptable?

No. In this temporal relative form, the -ka- element is required: wa-ta-ka-po-ingia. Forms like “watapoingia” are not standard.

What’s the difference between watakapoingia and watakaoingia?

watakapoingia = when they will enter (temporal clause)
watakaoingia = those who will enter (relative clause describing people)
Example: Wageni watawakaribisha wale watakaoingia = Guests will welcome those who will enter.

Can I front the when-clause?

Yes, very idiomatic:
Bi harusi na bwana harusi watakapoingia, wageni watapiga makofi.
Same meaning, sometimes even clearer for learners.