Learn Hardcore Swahili: Ratiba ya mitihani imetundikwa ukutani, karibu na saa ya ukutani. - The exam schedule has been hung on the wall, near the wall clock.

Imetundikwa ukutani… – “It has been hung on the wall…”
Focus: the schedule and its location. The person who hung it is not important.
Wameitundika ratiba ya mitihani ukutani… – “They have hung the exam schedule on the wall…”
Focus: they (the doers) and the action they did.

In this sentence, the important information is where the exam schedule is, not who hung it. That’s why the passive imetundikwa is natural and common.

What exactly does ya mean in ratiba ya mitihani, and which word controls its form?

Ya here is the “of” word; it links two nouns:

ratiba ya mitihani = “the schedule of exams.”

Important: the form of this ya is controlled by the first noun (the thing being “possessed”), not the second one.

First noun (possessed): ratiba (schedule) – class 9, singular.
Second noun: mitihani (exams) – class 4, plural.

Because ratiba is class 9 singular, the correct possessive is ya:

ratiba ya mitihani – schedule of exams.

If the first noun changed class, ya would change too, for example:

mpango wa mitihani – “plan of the exams” (mpango, class 3 → wa)
ratiba za mitihani – “timetables of the exams” (plural ratiba, class 10 → za)

Why is it ratiba ya mitihani, not ratiba za mitihani or ratiba wa mitihani?

Because of noun class and number:

ratiba here is singular (one timetable), class 9.
Class 9 singular takes ya for “of”:
- ratiba ya mitihani – “the exam schedule.”

Other forms would change the meaning or be ungrammatical:

ratiba za mitihani – plural: “exam timetables” (several schedules).
Still correct Swahili, but a different meaning.
ratiba wa mitihani – wrong, because wa is used with other classes (e.g. class 1 and 3), not with class 9.

So ya is correct because we are talking about one schedule (class 9 singular).

What are the singular and plural forms of mitihani and ratiba?

Mitihani

Singular: mtihani – “exam, test.”
Plural: mitihani – “exams, tests.”

Class: 3/4 (mtihani / mitihani).

Ratiba

Singular: ratiba – “timetable, schedule.”
Plural: ratiba – “timetables, schedules.”

Class: 9/10 (ratiba / ratiba).
You know whether it’s singular or plural from context and from agreement:

ratiba imeletwa – singular (class 9) → ime-
ratiba zimeletwa – plural (class 10) → zime-

What does the -ni in ukutani do, and how is ukuta different from ukutani?

The -ni on a noun usually makes it a locative form (“at / in / on [that noun]”).

ukuta – “wall.”
ukutani – “at the wall / on the wall / by the wall.”

So:

imetundikwa ukutani = “it has been hung on the wall.”

Compare:

ukuta mweupe – “a white wall” (wall as an object/thing).
wanaimba ukutani – “they are singing at/by the wall” (wall as a place).

In many cases you could also say kwenye ukuta with a similar meaning:

imetundikwa kwenye ukuta – “it has been hung on the wall.”

Could you also say kwenye ukuta instead of ukutani? Is there a difference?

Yes, kwenye ukuta is fine and very common. Both are grammatical:

imetundikwa ukutani – uses the locative suffix -ni.
imetundikwa kwenye ukuta – uses the preposition kwenye (“in/at/on”) plus the basic noun ukuta.

Nuance:

ukuta → thing (“a wall”).
ukutani / kwenye ukuta → location (“on/at the wall”).

In everyday speech, ukutani and kwenye ukuta usually feel interchangeable in this kind of sentence.

What does karibu na mean here, and how is it different from karibu by itself?

In this sentence:

karibu na saa ya ukutani = “near the wall clock.”

Karibu has several uses in Swahili:

As a preposition/adverb of place
- karibu na X – “near/close to X.”
- karibu na nyumba – “near the house.”
As an interjection: “welcome”
- Someone enters your house: you say Karibu!
As “almost, nearly” (in some contexts)
- Karibu nikaanguka – “I almost fell.”

In your sentence, it’s use (1): karibu na = “near.”
You could also sometimes hear karibu na ukuta (“near the wall”), etc.

What does saa ya ukutani literally mean, and why does it mean “the wall clock”?

Literally, saa ya ukutani is:

saa – “hour / clock / watch.”
ya – “of” (agreeing with saa, a class 9 noun).
ukutani – “on/at the wall.”

So word-for-word: “the clock of the (place) on the wall”, i.e. “the clock that is on the wall.”

Swahili often uses such “of + locative” constructions to express something like English compound nouns:

kiti cha plastiki – “plastic chair” (chair of plastic).
saa ya ukutani – “wall clock” (clock on the wall).

You could also say:

saa ya ukuta – “clock of the wall” (still understandable).
saa ya kuwaning’inia ukutani – more descriptive, “clock that hangs on the wall,” but not necessary in normal speech.

Saa ya ukutani is the natural phrase for “the wall clock.”

Why is it saa ya ukutani, not saa ya ukuta?

You could say saa ya ukuta, and people would understand, but:

ukuta = the wall (as an object).
ukutani = at/on the wall (as a location).

By saying saa ya ukutani, you are really saying “the clock that is at/on the wall,” which matches how we understand “wall clock” – a clock that hangs in that location.

So:

saa ya ukuta – “clock of the wall” (less idiomatic).
saa ya ukutani – “clock on the wall” (natural, common).

What tense or aspect does -me- in imetundikwa express, and how is it different from -li-?

The -me- marker expresses a completed action with present relevance, similar to the English present perfect:

imetundikwa ukutani – “it has been hung on the wall (and is now there).”

If you used -li- instead:

ilitundikwa ukutani – “it was hung on the wall.”

Nuance:

-me-: completed and the result still matters now (the schedule is currently on the wall).
-li-: simple past; focuses on the fact that the action happened in the past, without highlighting the current result.

In your sentence, -me- fits well because the speaker is telling you where the schedule is now.

What are the noun classes of ratiba, mtihani/mitihani, saa, and ukuta, and how do we see their effects in this sentence?

Here is a quick overview:

ratiba – “schedule, timetable”
- Class: 9/10.
- In the sentence:
  - Subject marker on the verb: i- → imetundikwa.
  - Possessive “of”: ya → ratiba ya mitihani.
mtihani / mitihani – “exam / exams”
- Class: 3/4 (mtihani / mitihani).
- In the sentence:
  - No direct agreement shown, but if there were, plural mitihani would take ya for “of,” e.g. mitihani ya mwisho (“final exams”).
saa – “hour / clock / watch”
- Class: 9/10.
- In the sentence:
  - Possessive “of” is ya → saa ya ukutani.
ukuta – “wall”
- Class: often treated as 11/10 (ukuta / kuta).
- In the sentence:
  - It appears in the locative form ukutani (wall as a place).
  - That locative form doesn’t trigger additional agreement here; it just functions as a location.

These class patterns explain why we see i-, ya, and ukutani in exactly those forms in the sentence.