Usiku wa baridi, mimi hupaka krimu usoni na losheni miguuni kabla ya kulala.

Wa is a linking word, often called the associative marker. It connects usiku and baridi.

So usiku wa baridi is literally something like night of cold, but in natural English it means a cold night or, in this sentence, more naturally on cold nights.

The form wa is not random; it matches the noun class of usiku in this kind of construction.

Grammatically, usiku is singular, but in context it can be generic.

Because the verb uses hu-, which shows a habitual action, the whole sentence is understood as something that happens regularly. So the phrase is best understood as:

• on cold nights
• when the night is cold
• on a cold night, in a general sense

It does not have to mean one specific night.

In many Swahili tenses, the verb itself shows the subject clearly. But with the habitual hu- form, the normal subject prefix is not used in the usual way.

So hupaka by itself does not clearly show I the way napaka would. That is why mimi is helpful here: it makes the subject explicit.

So:

• mimi hupaka = I usually apply
• hupaka by itself could sound incomplete or depend heavily on context

Hu- marks a habitual or customary action.

So mimi hupaka means:

• I usually apply
• I tend to apply
• I apply regularly

It is different from napaka, which would more naturally suggest:

• I am applying
• I apply in a more immediate or less specifically habitual sense

Here, hu- is important because the sentence describes a routine.

Here kupaka means to apply, to spread on, or to put on the surface of something.

It is a very natural verb for things like:

• cream
• lotion
• oil
• makeup
• paint

So hupaka krimu usoni is literally usually applies cream on the face.

Because Swahili often uses the locative ending -ni instead of a separate preposition.

So:

• uso → usoni = on the face / at the face
• miguu → miguuni = on the feet / at the feet

The ending -ni is locative, so it often covers meanings like:

• in
• on
• at
• sometimes to

In this sentence, the best English translation is on the face and on the feet.

Because miguu is the basic noun meaning feet, while miguuni is the locative form.

So:

• miguu = feet
• miguuni = on the feet / at the feet

The noun keeps its stem and adds the locative ending -ni.

Yes. They are common loanwords in Swahili, adapted from English:

• krimu ← cream
• losheni ← lotion

This is very normal in Swahili, especially for modern items, cosmetics, toiletries, and technical vocabulary.

So even though they come from English originally, they function as ordinary Swahili nouns here.

Here na means and.

It links two parallel parts:

• krimu usoni
• losheni miguuni

So the structure is:

• apply cream to the face and lotion to the feet

Swahili na can also mean with in other contexts, so this is a very common point of confusion for learners. In this sentence, it is clearly and.

Kabla ya means before.

After it, Swahili often uses a noun or an infinitive phrase. Here, kulala is the infinitive to sleep, but in English we usually translate it more naturally as:

• before sleeping
• before going to sleep
• before bed

So:

• kabla ya kulala = before sleeping / before going to sleep

The ya is part of the normal pattern kabla ya.

Because after kabla ya, Swahili very often uses the infinitive when the meaning is general or when the subject is understood from context.

So kabla ya kulala is a compact way to say before sleeping.

You do not need to repeat mimi or use a full finite verb there, because the main clause already tells us who is doing the action.

The word order can be changed.

Placing Usiku wa baridi first sets the time frame right away, a bit like saying:

• On cold nights, ...

That is very natural. But you could also move it later if needed. Swahili allows fairly flexible placement of time expressions, especially when they are used to set the scene.

So the fronted version is natural and emphasizes the circumstance under which this routine happens.