Learn Hardcore Swahili: Wakati rafiki yako alipiga simu, wewe ulikuwa ukila chakula cha mchana? - When your friend called, were you eating lunch?

A time (when-) clause:
Wakati rafiki yako alipiga simu
→ When your friend called
A main clause:
wewe ulikuwa ukila chakula cha mchana
→ you were eating lunch

Swahili often puts the time clause first, followed by a comma, then the main clause. You could also put the main clause first without changing the meaning much:

Ulikuwa ukila chakula cha mchana wakati rafiki yako alipiga simu?
→ Were you eating lunch when your friend called?

Why do we have both ulikuwa and ukila? Isn’t one verb enough to say “you were eating”?

Together ulikuwa ukila expresses past continuous (you were eating), not just a simple past (you ate).

Breakdown:

u-li-kuwa
- u- = you (2nd person singular subject)
- -li- = past tense (simple/completed past)
- -kuwa = be
  → ulikuwa = you were
u-ki-la
- u- = you (again, each verb needs its own subject marker)
- -ki- = continuous / “while doing” aspect marker
- -la = eat (root is -la, usually written as kula in infinitive)
  → ukila = (you) were eating / (you) while eating

So:

ulila chakula cha mchana = you ate lunch (a completed event)
ulikuwa ukila chakula cha mchana = you were eating lunch (ongoing at some moment in the past)

The sentence is specifically asking about an ongoing action at the time of the phone call, so it uses ulikuwa ukila, not ulila.

What exactly does ki in ukila do, and why not use na as in ulikuwa unakula?

The -ki- here is a continuous / simultaneous aspect marker: it highlights that the action was in progress at the same time as something else.

u-ki-la: you + -ki- (ongoing) + eat → (you) were eating / while you were eating

Many learners first meet -na- as the “present continuous”:

una-kula = you are eating (now)

In the past continuous, Swahili has two common patterns:

Standard / textbook-like
- ulikuwa ukila = you were eating
  (kuwa in the past + -ki- on the main verb)
Very common in speech
- ulikuwa unakula = you were eating
  (kuwa in the past + -na- on the main verb)

Both are widely used. Many grammars prefer -ki- for this “ongoing while something else happened” sense; everyday speech often uses -na- too.

Note: ukila without ulikuwa can also mean “if/when you eat”, depending on context. With ulikuwa, it’s clearly part of past continuous.

Why is the pronoun wewe used? Isn’t the u- in ulikuwa and ukila already saying “you”?

Yes, the u- on ulikuwa and ukila already marks the subject as “you (singular)”, so wewe is not grammatically required.

Wakati rafiki yako alipiga simu, ulikuwa ukila chakula cha mchana?
is perfectly correct.

Putting wewe in:

Wakati rafiki yako alipiga simu, wewe ulikuwa ukila chakula cha mchana?

adds emphasis or contrast, roughly like:

When your friend called, *were you the one who was eating lunch (as opposed to someone else)?*

Speakers use the full pronoun (wewe, yeye, sisi, ninyi, wao) for:

emphasis/contrast, or
clarity, if the subject might be ambiguous.

Why is it rafiki yako and not rafiki wako for “your friend”?

In Swahili, the form of “your” changes with the noun class of the noun it modifies.

rafiki (friend) is treated as a class 9 noun in standard grammar.
Class 9 uses possessives with a y-:
- rafiki yako = your friend
- nyumba yako = your house

By contrast, nouns in class 1 (people like mtu, mwalimu) take w-:

mtu wako = your person
mwalimu wako = your teacher

So:

rafiki yako = “your friend” (correct for class 9)

You will sometimes hear rafiki wako from some speakers, but rafiki yako is the standard/normative form.

What does alipiga simu literally mean, and why does it mean “(he/she) called”?

Breakdown:

a-li-pig-a
- a- = he/she (3rd person singular subject)
- -li- = past tense
- -pig- = hit/strike/beat
- -a = final vowel
  → alipiga = he/she hit/struck
simu = phone / telephone (and by extension, a phone call)

So kupiga simu literally means “to hit/strike the phone”, but idiomatically it means “to make a phone call / to call (on the phone)”.

This is just like English using a literal verb in a fixed expression, e.g.:

“pick up the phone” (you are not literally picking it off the ground in many cases)
“ring someone up”

In Swahili, to say “to phone someone”, the normal verb is kupiga simu, not using kuita (which is “to call out / to summon / to name”).

How would I say explicitly “when your friend called you” rather than just “when your friend called”?

To make you explicit as the person called, you add an object marker and often the suffix -ia on the verb:

Wakati rafiki yako alikupigia simu…
- a-li-ku-pig-ia
  - a- = he/she
  - -li- = past
  - -ku- = you (object)
  - -pig- = hit/strike
  - -ia = “to/for someone” (applicative suffix)
→ When your friend called you (on the phone)…

Compare:

alipiga simu = he/she made a phone call (unspecified who to)
alikupigia simu = he/she called you (on the phone)

So, if you really want to say “called you”, alikupigia simu is the clear form.

How do we know this is a question in Swahili? There is no je, and the word order looks like a statement.

In Swahili, yes/no questions often have exactly the same word order as statements. The difference is:

speech: rising intonation at the end
writing: a question mark ?

So:

Wakati rafiki yako alipiga simu, ulikuwa ukila chakula cha mchana.
→ statement
Wakati rafiki yako alipiga simu, ulikuwa ukila chakula cha mchana?
→ question (by intonation and the question mark)

You can add je for extra clarity or formality:

Je, wakati rafiki yako alipiga simu, ulikuwa ukila chakula cha mchana?

But je is optional here; the version without je is completely normal.

Can I change the order of the clauses, like putting the “when” part at the end?

Yes. The time clause with wakati can go either before or after the main clause.

All of these are acceptable:

Wakati rafiki yako alipiga simu, ulikuwa ukila chakula cha mchana?
Ulikuwa ukila chakula cha mchana wakati rafiki yako alipiga simu?
Ulikuwa ukila chakula cha mchana, wakati rafiki yako alipiga simu? (comma optional)

The basic meaning stays the same: you’re asking whether you were eating lunch at the time your friend called. Changing the order mainly affects what feels like the topic or what is highlighted first, but not the core meaning.

Why is it chakula cha mchana for “lunch”? What does cha do here?

Chakula cha mchana is literally “food of daytime/afternoon”, i.e. the midday meal → lunch.

chakula = food / a meal (class 7)
mchana = daytime / afternoon

The word cha is a genitive/possessive connector meaning “of”, and its form depends on the noun class of the first noun. For class 7 (ki/vi class):

singular (class 7): cha
plural (class 8): vya

So:

chakula cha mchana = lunch (food of the afternoon)
chakula cha asubuhi = breakfast (food of the morning)
chakula cha jioni / chakula cha usiku = supper / dinner (evening/night meal)
vyakula vya mchana = lunches (midday meals)

Here, cha just links chakula and mchana in a “X of Y” relationship.