Watoto waliona kijito kidogo karibu na shamba.

Because watoto is the plural form, meaning children. The singular is mtoto, meaning child.

This noun belongs to the m-/wa- noun class pattern for people:

• mtoto = child
• watoto = children

So the sentence starts with a plural subject.

Waliona can be broken down like this:

• wa- = they (subject prefix for plural people)
• -li- = past tense marker
• -on- = verb root meaning see
• -a = final vowel

So:

• wa-li-on-a = they saw

This is a very common Swahili verb pattern: subject prefix + tense marker + verb root + final vowel

In Swahili, adjectives usually come after the noun they describe.

So:

• kijito kidogo = small stream
• literally: stream small

This is normal Swahili word order.

Because Swahili adjectives usually agree with the noun class of the noun they modify.

Kijito belongs to the ki-/vi- noun class, so the adjective -dogo gets the matching class prefix:

• kijito = stream
• kidogo = small

That matching ki- shows agreement.

This is an important feature of Swahili grammar: words connected to a noun often change form to match its noun class.

Yes, kijito usually refers to a small river, brook, or stream. It already has a diminutive sense.

So kijito kidogo can feel a bit like saying:

• a small stream
• or even a very small little stream

It is still perfectly natural, because kidogo adds extra emphasis to the smallness.

Karibu na means near or close to.

In this sentence:

• karibu na shamba = near the farm / near a farm

The word na is normally used after karibu when a noun follows.

So learners should remember this as a chunk:

• karibu na = near

Yes, na often means and or with, but here it is part of the expression karibu na, which means near.

So in this sentence, you should not translate it word-for-word as near and farm. Instead, treat it as one expression:

• karibu na shamba = near the farm

This is very common in Swahili: a word can have slightly different functions depending on the expression it appears in.

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

So:

• watoto can mean the children or just children
• kijito kidogo can mean a small stream or the small stream
• shamba can mean a farm or the farm

The exact meaning depends on context.

The sentence follows a very common Swahili pattern:

• Subject + Verb + Object + Other information

Here that is:

• Watoto = subject
• waliona = verb
• kijito kidogo = object
• karibu na shamba = location phrase

So the structure is:

• The children
  • saw
    • a small stream
      • near the farm

This is quite close to normal English word order.

Here are the forms:

• mtoto = child

• watoto = children

• kijito = stream / small river

• vijito = streams

• shamba = farm / field
• mashamba = farms / fields

Learning singular-plural pairs is very helpful in Swahili, because noun class affects agreement elsewhere in the sentence.

Swahili pronunciation is usually very regular.

For these words:

• waliona = wa-li-o-na
• kijito = ki-ji-to

A few useful points:

• Each vowel is pronounced clearly.
• io in waliona is pronounced as two vowels, not merged into one.
• Stress in Swahili usually falls on the second-to-last syllable.

So roughly:

• waliONA
• kiJIto

Yes, but it would mean something slightly different.

• waliona = they saw (simple past)
• wameona = they have seen / they saw with a stronger sense of present relevance or a completed action connected to now

So:

• Watoto waliona... = a straightforward past event
• Watoto wameona... = the children have seen..., often implying the result matters now

Both are grammatical, but waliona is the normal simple past form in your sentence.