Learn Hardcore Swahili: Sauti ya kwaya inasikika ukumbini. - The sound of the choir is heard in the hall.

i- = subject marker for class 9 (agreeing with sauti)
-na- = present tense/aspect
-sikik- = verb stem from -sikika “to be heard, be audible” (a stative/ability form built from -sikia “to hear” with the -ik- extension)
-a = final vowel

So inasikika is “it (class 9) is audible.”

Why is the subject prefix i- used and not a-?

Because sauti is a class 9 noun, and class 9 takes the subject marker i- in the present (i-na-…). The a- / ana- marker is for class 1 (human) nouns. Compare:

Sauti inasikika... (class 9)
Mwalimu anasikika... (class 1)

What does ya do in sauti ya kwaya?

Ya is the associative “of.” In Swahili, “of” agrees with the head noun. The head is sauti (class 9), so you use ya: sauti ya kwaya = “sound of (the) choir.” If the head noun were in other classes, the form changes, for example:

Class 9/10: ya (sg), za (pl) → sauti ya/za...
Class 7/8: cha, vya → kiti cha… / viti vya…
Class 5/6: la, ya → tunda la… / matunda ya…
Class 3/4: wa, ya → mti wa… / miti ya…
Class 1/2: wa → mtu wa… / watu wa…

Could I just say Kwaya inasikika ukumbini instead?

Yes. Kwaya inasikika ukumbini means “The choir is audible in the hall.” The difference is focus:

Sauti ya kwaya... emphasizes the sound itself.
Kwaya... emphasizes the group as the source.

Both are grammatical and natural.

What does ukumbini mean exactly? Why the -ni?

Ukumbini = “in/at the hall.” It’s ukumbi (hall) + the locative suffix -ni, which often means “in/at/on.” You could also use prepositions:

katika ukumbi or kwenye ukumbi = “in the hall”
ndani ya ukumbi = “inside the hall” (emphasizes interior)

-ni is compact and very common.

Does ukumbini mean the sound is coming from the hall, or that it’s heard there?

It locates where it’s heard (the place of audibility). To say the sound comes from the hall, use a source phrase: Sauti ya kwaya inasikika kutoka ukumbini (“…is heard from the hall”).

What’s the difference between -sikia, -sikika, and -sikiliza?

-sikia = “to hear” (someone hears something)
-sikika = “to be heard, be audible” (no agent; a stative/possibility sense)
-sikiliza = “to listen (to)” (active, intentional listening) So inasikika is about audibility, not someone hearing or listening.

How would I negate the sentence?

Use the negative subject marker and final -i:

Sauti ya kwaya haisikiki ukumbini. Breakdown: ha- (neg) + i- (class 9 subj) → hai-, verb stem -sikik-, negative final -i.

How do I put it in past, future, or habitual?

Past: Sauti ya kwaya ilisikika ukumbini.
Perfect (result/recent past): Sauti ya kwaya imesikika ukumbini.
Future: Sauti ya kwaya itasikika ukumbini.
Habitual/general truth: Sauti ya kwaya husikika ukumbini.

If I want to say “the choir’s voices are heard,” how do I make everything agree in the plural?

Make the head noun plural and adjust agreement:

Sauti za kwaya zinasikika ukumbini. Changes:
sauti (class 10 plural) → associative za
Verb subject marker zi- for class 10 → zinasikika

Why is there no “the” in the Swahili sentence? How do I show definiteness?

Swahili doesn’t use articles. Sauti ya kwaya inasikika ukumbini can mean “the sound…” or “a sound…” depending on context. To force specificity you can add words like:

hii/ile (this/that): sauti hii/ile ya kwaya
moja (one/a certain): sauti moja ya kwaya
fulani (a certain): sauti fulani ya kwaya

Can I front the location for emphasis?

Yes. For topicalization:

Ukumbini, sauti ya kwaya inasikika. This highlights the place first; the meaning stays the same.

Is kwaya a loanword, and how do I pronounce it?

Yes, it’s a loanword corresponding to English “choir.” Pronounce it as two syllables: kwa-ya (the y is a consonant glide). It’s class 9, so it takes class 9 agreement: kwaya inasikika, not kwaya anasikika.

Could I say ukumbi without -ni?

Not by itself to mean “in the hall.” Without -ni, you need a preposition:

katika ukumbi / kwenye ukumbi With -ni, ukumbini already encodes the location, so no extra preposition is needed.