Bili za huduma ziko mezani.

Many loanwords in Swahili belong to noun classes 9/10, and in those classes the singular and plural often have the same form.

So:

• bili = bill or bills
• the other words in the sentence show whether it is singular or plural

In your sentence, ziko and za show that bili is being treated as plural.

For comparison:

• Bili ya huduma iko mezani. = The utility bill is on the table.
• Bili za huduma ziko mezani. = The utility bills are on the table.

za huduma means something like of services or for services.

Here:

• za = a connector meaning of/for, agreeing with a plural class 10 noun
• huduma = service, services, or in context utilities

So bili za huduma means:

• service bills
• utility bills

The most natural English translation in many contexts is utility bills.

Because za must agree with bili, which is plural here.

In Swahili, words like of change form depending on the noun class of the noun they describe.

With bili:

• singular: bili ya huduma
• plural: bili za huduma

So:

• ya = singular agreement here
• za = plural agreement here

This is part of the Swahili noun class system.

ziko means they are in the sense of they are located or they are present.

It is made of:

• zi- = subject marker for plural class 10 nouns
• -ko = a locative form of be

So ziko mezani literally means something like:

• they are on the table
• they are located on the table

This is why ziko is used instead of a single general word for are.

Swahili often uses different forms of be depending on the situation.

• ni is often used for identification:
  
  • Yeye ni mwalimu. = He/She is a teacher.
• -ko forms like iko, ziko, niko are often used for location:
  
  • Kitabu kiko mezani. = The book is on the table.
  • Vitabu viko mezani. = The books are on the table.

Since this sentence talks about where the bills are, ziko is the correct choice.

mezani means on the table or at the table, depending on context.

It comes from:

• meza = table
• -ni = a locative ending meaning in/on/at

So:

• meza = table
• mezani = on the table / at the table

The exact English preposition depends on context. In this sentence, on the table is the natural translation.

Swahili does not usually use articles like a, an, or the.

So bili can mean:

• a bill
• the bill
• bills
• the bills

The context tells you which meaning is intended.

That is why Bili za huduma ziko mezani can naturally be translated as The utility bills are on the table, even though there is no separate word for the.

Mostly yes. The basic order here is:

• Bili za huduma = subject noun phrase
• ziko mezani = predicate

So the structure is roughly:

• Utility bills
  • are on the table

This is very similar to English:

• The utility bills are on the table.

Yes. Huduma is a broad word that usually means service or services.

Depending on context, bili za huduma could mean:

• service bills
• bills for services
• utility bills

If the context is household expenses like electricity, water, internet, or gas, then utility bills is the most natural English meaning.

You would say:

Bili ya huduma iko mezani.

The changes are:

• za → ya for singular agreement
• ziko → iko for singular agreement

So:

• Bili ya huduma iko mezani. = The utility bill is on the table.
• Bili za huduma ziko mezani. = The utility bills are on the table.

Not always. The locative ending -ni can cover meanings like:

• in
• on
• at

So mezani could mean:

• on the table
• at the table

In this sentence, because bills are physical objects resting on a surface, on the table is the best translation.