Mara tu majirani watakapofika, tutaanza kuzoa taka.

Mara tu means as soon as or once.

• mara can relate to time/occasion
• tu often adds the sense of just or immediately

So together, mara tu introduces something that happens right after another event.

Because majirani means neighbors, and it refers to people, the verb uses the plural subject marker wa-, which is the normal marker for they when talking about people.

So in watakapofika:

• wa- = they
• and it agrees with majirani

Even if a noun’s shape is not what an English speaker expects, verbs in Swahili must still agree with the noun.

It can be broken down like this:

• wa- = they
• -takapo- = when they will / at the time when
• fika = arrive

So watakapofika means something like:

when they arrive or more literally, when they will have arrived / at the future time when they arrive

This is a very common Swahili way to express a future when-clause.

The -po- here is part of a time-related verb form used for meanings like when, at the time that, or once in future situations.

So:

• watafika = they will arrive
• watakapofika = when they arrive

That means -po- helps turn the verb into a clause referring to a future time point.

You may hear simpler alternatives in everyday speech, but watakapofika is the more standard and grammatically precise form after a future time expression like mara tu.

Compare:

• majirani watafika = the neighbors will arrive
• majirani watakapofika = when the neighbors arrive

So watafika is a plain future statement, while watakapofika is a time clause.

Tutaanza breaks down like this:

• tu- = we
• -ta- = future
• anza = begin/start

So tutaanza means we will start or we will begin.

After verbs like anza (begin/start), Swahili normally uses the infinitive form of the next verb.

So:

• tutaanza = we will start
• kuzoa = to collect / to pick up / to gather

Together:

tutaanza kuzoa taka = we will start collecting garbage

This is similar to English start to collect.

In this sentence, zoa means collect, gather up, or pick up, especially things like dirt, litter, or garbage.

So kuzoa taka is a natural way to say something like:

• to collect trash
• to pick up rubbish
• to clean up garbage

The exact English translation depends on context.

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

So taka can mean:

• garbage
• trash
• rubbish
• sometimes waste

Also, nouns in Swahili do not show plural in the same way English does. You understand the meaning from the noun itself and from context.

So taka here works fine without anything corresponding to the garbage or garbages.

Yes. This sentence puts the time clause first:

Mara tu majirani watakapofika, tutaanza kuzoa taka.

But you could also say:

Tutaanza kuzoa taka mara tu majirani watakapofika.

Both are natural. Putting mara tu... first gives extra emphasis to the timing: as soon as the neighbors arrive.

The comma is helpful in writing because the sentence begins with a time clause:

Mara tu majirani watakapofika, tutaanza kuzoa taka.

It separates:

1. the when/as soon as part
2. the main statement

In speech, the pause may be small or even absent, but in writing the comma is perfectly normal.