Ukifika nyumbani, safisha mikono yako kwa sabuni.

Ukifika can be broken down like this:

• u- = you (singular)
• -ki- = a marker often meaning if or when
• fik- = the verb root arrive
• -a = the final vowel

So ukifika literally means something like if/when you arrive.

It can mean either, depending on context.

The marker -ki- is often used for:

• if
• when
• sometimes whenever

In this sentence, because it is giving a general instruction, English usually translates it as when you arrive home rather than if you arrive home.

Nyumbani comes from nyumba meaning house/home plus the locative ending -ni.

So nyumbani means something like:

• at home
• home
• sometimes to home/homeward, depending on the verb

With kufika (to arrive), ukifika nyumbani naturally means when you arrive home.

Yes. Safisha is the singular imperative form of kusafisha, meaning to clean.

In Swahili, the singular command form of many verbs is just the verb stem:

• safisha! = clean!
• soma! = read!
• funga! = close!

So here safisha mikono yako means clean/wash your hands.

Not exactly. Safisha more literally means clean.

A very common verb for wash is osha. So a learner may expect osha mikono yako kwa sabuni.

However, in this context, clean your hands with soap is naturally understood in English as wash your hands with soap. So the translation makes sense, even though the Swahili verb is more literally clean.

Because mikono is plural.

• mkono = hand/arm
• mikono = hands/arms

Since people normally wash both hands, the plural mikono is used.

This is also a good example of a Swahili noun class pattern:

• singular: m-
• plural: mi-

So:

• mkono
• mikono

In Swahili, possessives usually come after the noun, not before it.

So:

• mikono yako = your hands
• literally: hands your

Also, yako agrees with the noun mikono, not just with the person being referred to. The possessive stem here is -ako (your, singular), and it takes the right agreement form for mikono.

Compare:

• mkono wako = your hand
• mikono yako = your hands

Kwa sabuni means with soap or using soap.

Here kwa shows the means or instrument used to do something. In other words, it tells you how the hands should be cleaned.

Some similar examples:

• kwa maji = with water
• kwa kisu = with a knife
• kwa gari = by car

So kwa sabuni = with soap.

Swahili usually does not use articles like English a/an and the.

Instead, the meaning is understood from context.

So mikono yako already clearly means your hands, without needing a separate word for the. This is very normal in Swahili.

To address more than one person, you would usually change both the subject and the command:

Mkifika nyumbani, safisheni mikono yenu kwa sabuni.

Changes:

• ukifika → mkifika = when you all arrive
• safisha → safisheni = plural command
• yako → yenu = your (plural)

In many situations, the plural form can also sound more polite when speaking to one person.