Learn Hardcore Swahili: Umati mkubwa ulifika kwenye tukio la kijamii kitongojini angalau saa moja kabla. - A large crowd arrived at the community event in the neighborhood at least an hour early.

Because the subject is umati (crowd), which is grammatically singular and belongs to noun class 11 (u-). Class 11 takes the subject prefix u-, so the verb is u-li-fika → ulifika. Walifika would agree with class 2 plural (they), not with class 11.

What are the parts of the verb ulifika?

u- = subject prefix for class 11 (agreeing with umati)
-li- = past tense marker
-fika = verb stem “arrive” Together: u-li-fika → “(it) arrived.”

What noun class is umati, and how does that affect other words?

Umati is class 11 (u-). Agreement shows up like this:

Subject prefix on verbs: u- (ulifika)
Common adjective agreement: m- (e.g., umati mkubwa “a big crowd”)
The connective “of” (-a): usually wa with class 11 (e.g., umati wa watu “a crowd of people”)

Why is it mkubwa and not ukubwa?

Mkubwa is the adjective “big,” with the class-11 adjective prefix m-. Ukubwa is a noun meaning “size/greatness.” Here we need an adjective agreeing with umati, so mkubwa is correct.

What does kwenye mean here, and could I use another preposition?

Kwenye is a general preposition meaning “at/in/on/to.” You could also say:

katika (more formal/literary): … alifika katika tukio …
Use the locative suffix -ni on the place noun instead of a preposition when appropriate. Avoid kwa here; kwa is typically “by/with/at someone’s place” and is not used with tukio in this sense.

Is kwenye redundant with the -ni in kitongojini?

No. In this sentence kwenye goes with tukio (“to/at the event”), and kitongojini (“in the neighborhood/suburb”) further specifies which event. It’s not “kwenye kitongojini” but “kwenye tukio … kitongojini.”

What does the -ni in kitongojini do?

The suffix -ni marks a locative: kitongoji → kitongojini = “in/at the neighborhood (suburb/hamlet).” You could also say katika kitongoji with the same meaning.

Why is it la kijamii and not ya kijamii or cha kijamii?

The connective “of” is the -a linker and must agree with the head noun tukio, which is class 5. Class 5 takes la, hence tukio la …. If it were plural (class 6: matukio), you’d use ya: matukio ya kijamii. Cha would be for class 7 nouns.

Does kijamii change to agree with tukio?

No. Kijamii is a relational adjective derived from jamii (“society”) and is typically invariable across classes and number. Agreement is carried by the linker (la/ya/cha…) before it, not by changing kijamii itself.

Is kabla correct without ya here?

Yes. … saa moja kabla is idiomatic for “an hour early/ beforehand.” Use kabla ya when you specify the event you’re earlier than:

saa moja kabla ya tukio (an hour before the event)
saa moja kabla ya kuanza (an hour before starting)

How do I say “at least two hours early” (or other amounts)?

“At least two hours early”: angalau saa mbili kabla (also heard: angalau masaa mawili kabla)
“At least thirty minutes early”: angalau dakika thelathini kabla

Where can the time phrase go in the sentence?

Flexible positions are fine:

End (as given): … angalau saa moja kabla.
Beginning: Angalau saa moja kabla, umati mkubwa ulifika …
After the verb: … ulifika angalau saa moja kabla kwenye tukio … Keep it near the verb for clarity.

Could I use uliwasili instead of ulifika?

Yes. -wasili also means “arrive,” often a bit more formal or “official” than -fika. So umati mkubwa uliwasili … is a natural variant.

What if I want to talk about multiple events instead of one event?

Make tukio plural (class 6) and adjust agreement:

… kwenye matukio ya kijamii … (events) Note the linker changes from la (class 5) to ya (class 6).

Is kitongoji the only word for “neighborhood,” and how does it differ from mtaa?

Kitongoji: suburb/hamlet or neighborhood unit (often administrative; class 7/8: kitongoji/vitongoji).
Mtaa: urban neighborhood/block/ward (class 3/4: mtaa/mitaa), common in city contexts. Both can translate “neighborhood,” but mtaa is more urban; kitongoji often suggests a suburb/hamlet.