Huduma za usafirishaji wa vifurushi zimechelewa.

Because huduma is being treated as a plural noun in this sentence: services rather than service.

In Swahili, the connector meaning of changes form to agree with the noun before it. Here:

• huduma = services
• za = of for this noun class in the plural

So huduma za usafirishaji means something like shipping/delivery services.

A useful comparison:

• huduma ya usafirishaji = the shipping service / a shipping service
• huduma za usafirishaji = shipping services

The form of huduma itself does not change, so the agreement word za helps show that it is plural here.

Both za and wa can mean of, but they agree with different nouns.

In this sentence:

• huduma za usafirishaji
• usafirishaji wa vifurushi

The first connector, za, agrees with huduma.
The second connector, wa, agrees with usafirishaji.

So the structure is:

• huduma za X = services of X
• usafirishaji wa Y = transport/shipping of Y

Put together, it builds a chain:

• huduma → za usafirishaji
• usafirishaji → wa vifurushi

This is a very common Swahili pattern.

Usafirishaji is a noun meaning transport, shipping, or delivery depending on context.

It comes from the verb -safirisha, which means to transport, to ship, or to send/dispatch.

So:

• kusafirisha = to transport / to ship
• usafirishaji = transportation / shipping / delivery

In this sentence, usafirishaji wa vifurushi means the shipping/transport of parcels.

Vifurushi means parcels, packages, or packets.

It is the plural form of kifurushi:

• kifurushi = parcel / package
• vifurushi = parcels / packages

The change from ki- to vi- is a regular singular/plural pattern in Swahili noun classes. English speakers often notice this early because it is very common:

• kitabu → vitabu = book → books
• kiti → viti = chair → chairs
• kifurushi → vifurushi = parcel → parcels

Zimechelewa breaks down like this:

• zi- = subject prefix agreeing with plural huduma
• -me- = perfect aspect, often have
• -chelewa = be late / be delayed

So zimechelewa means they have become late, they are late, or they have been delayed, depending on context.

The key point is that zi- matches huduma as plural. That is why the verb is not umechelewa or imechelewa.

-me- usually marks the perfect in Swahili. It often corresponds to English have/has or a present result of a past event.

So:

• zimechelewa can mean have been delayed
• or are now delayed / are late

In other words, something happened earlier, and the result is true now.

This is why -me- is very natural in announcements or status updates.

Not exactly.

The verb -chelewa means to be late or to become delayed. So Swahili is not necessarily using a passive form here. It is more like saying:

• The services are late
• The services have become delayed

English often prefers have been delayed, but Swahili can express the same idea with -chelewa without needing a passive construction.

A more explicitly caused/passive idea would use a different verb, but zimechelewa is very normal and natural.

Yes. That would also be correct, but the focus shifts.

Compare:

• Huduma za usafirishaji wa vifurushi zimechelewa
  = the parcel shipping services are delayed

• Usafirishaji wa vifurushi umechelewa
  = the shipping/delivery of parcels is delayed

The first talks about the services.
The second talks more directly about the process/activity of parcel delivery.

So the difference is mostly one of focus and wording, not a completely different meaning.

Some Swahili nouns have the same form in both singular and plural. Huduma is one of them.

That means you often know whether it is singular or plural from the agreement words around it, not from the noun itself.

In this sentence, the plural is shown by:

• za after huduma
• zi- in zimechelewa

Those two signals tell you that huduma is being understood as services, not service.

A helpful way is to group the sentence like this:

Huduma | za usafirishaji | wa vifurushi | zimechelewa

Or more naturally:

Huduma za usafirishaji wa vifurushi = one big noun phrase
zimechelewa = the predicate

Inside that noun phrase:

• huduma za usafirishaji = shipping services
• usafirishaji wa vifurushi = shipping of parcels

So you can think of it as:

[services [of shipping [of parcels]]] have been delayed

That nested structure is very common in Swahili.

You would change the agreement words, not necessarily the noun huduma itself.

For singular:

• Huduma ya usafirishaji wa kifurushi imechelewa
  = the parcel shipping service has been delayed

Changes:

• za → ya because huduma is singular
• vifurushi → kifurushi if you mean one parcel
• zimechelewa → imechelewa because the subject is singular

So Swahili often shows singular/plural through agreement across the sentence rather than by changing every noun form.