Baada ya kutembea kwa muda mrefu, kifundo cha mguu wangu kiliuma kidogo.

Baada ya means after.

It is a very common way to introduce something that happens later than another action or event:

• baada ya chakula = after food / after the meal
• baada ya kazi = after work
• baada ya kutembea = after walking

So in this sentence, Baada ya kutembea kwa muda mrefu sets the time/background: After walking for a long time...

After baada ya, Swahili often uses the infinitive form of the verb, which begins with ku-.

• kutembea = to walk / walking

So:

• baada ya kutembea = after walking

This is very natural in Swahili. English uses after walking, and Swahili uses baada ya + infinitive.

Literally, it means something like for a long time.

Breakdown:

• kwa = for / in / by, depending on context
• muda = time, period
• mrefu = long

So:

• kwa muda mrefu = for a long time

It functions as an adverbial phrase telling you how long the walking lasted.

Kifundo cha mguu means ankle.

Literally, it is something like the joint of the leg/foot.

Breakdown:

• kifundo = joint, knuckle, ankle-joint type of structure
• cha = of
• mguu = leg / foot

In body vocabulary, mguu can refer to the lower limb, and the full phrase kifundo cha mguu is the normal way to say ankle.

Cha is the possessive/genitive linker meaning of, and it agrees with the noun before it.

Here, the head noun is kifundo, which is in the ki-/vi- noun class. For that class, the linker is cha.

So:

• kifundo cha mguu = ankle, literally joint of the foot/leg

This agreement is very important in Swahili:

• kitabu cha mwanafunzi = the student's book / book of the student
• kisu cha jikoni = kitchen knife, literally knife of kitchen

In Swahili, possessives normally come after the noun:

• mguu wangu = my leg / my foot
• kitabu changu = my book
• rafiki yangu = my friend

So:

• kifundo cha mguu wangu = my ankle

Literally, this is the ankle of my leg/foot.

The verb agrees with the subject, and the subject here is kifundo cha mguu wangu.

The head noun is kifundo, which belongs to the ki-/vi- noun class, so the subject prefix is ki-.

Breakdown of kiliuma:

• ki- = subject prefix for the ki-/vi- class
• -li- = past tense
• -uma = hurt / ache

So kiliuma means it hurt or it ached, with it referring to the ankle.

It can mean different things depending on context.

Common uses include:

• kuuma = to bite
• kuuma = to sting
• kuuma = to ache / hurt

In this sentence, because the subject is a body part (ankle), kiliuma clearly means:

• it hurt
• it ached

So this is a good example of how context determines the best translation.

Kidogo means a little / slightly here.

It modifies the verb phrase:

• kiliuma kidogo = it hurt a little / it ached slightly

Although kidogo often looks like an adjective in other contexts, it is very commonly used adverbially too.

Examples:

• Nimechoka kidogo. = I am a little tired.
• Alikasirika kidogo. = He/she got a little annoyed.
• Kiliuma kidogo. = It hurt a little.

Swahili often puts background or time information first, especially when setting the scene.

So:

• Baada ya kutembea kwa muda mrefu, kifundo cha mguu wangu kiliuma kidogo.

is very natural and means:

• After walking for a long time, my ankle hurt a little.

You could move things around in some contexts, but the sentence-initial time phrase sounds natural and clear.

Yes. Mguu can cover both leg and foot, depending on context.

That can feel strange to English speakers, because English separates them clearly. Swahili often relies on context or a longer expression:

• mguu = leg / foot
• kifundo cha mguu = ankle
• kidole cha mguu = toe

So in this sentence, there is no confusion because kifundo cha mguu clearly refers to the ankle.

You can, but it will sound less natural in English.

A very literal breakdown is:

• Baada ya = after
• kutembea = walking / to walk
• kwa muda mrefu = for a long time
• kifundo cha mguu wangu = the joint of my leg/foot
• kiliuma = it hurt
• kidogo = a little

A smoother English translation is:

• After walking for a long time, my ankle hurt a little.

That is the best way to understand the sentence naturally, while the literal breakdown helps you see the grammar.