Learn Hardcore Swahili: Leo jioni, mimi nitaweka vitabu vyetu kwenye meza. - This evening, I will put our books on the table.

ni- is a subject prefix attached to the verb: ni- + -ta- + -weka → nitaweka (I–FUTURE–put).
mimi is the independent pronoun I / me.

In normal sentences, the verb prefix is enough, so you can say:

Nitaweka vitabu vyetu kwenye meza. – perfectly correct.

Adding mimi gives emphasis or contrast, like:

Leo jioni, mimi nitaweka vitabu vyetu, si wewe.
(This evening, *I will put our books there, not you.*)

So mimi is optional and mainly used for emphasis, contrast, or clarity in conversation.

How is the verb nitaweka formed, exactly?

Nitaweka is built from three parts:

ni- → subject prefix for I
-ta- → future tense marker
-weka → verb root to put / to place

So:

ni- + -ta- + -weka → nitaweka = I will put / I will place

Some other examples:

utaweka – you (sg.) will put (u- + -ta- + -weka)
ataweka – he/she will put (a- + -ta- + -weka)
tutaweka – we will put (tu- + -ta- + -weka)

Could I say tutaweka instead of nitaweka if I mean we will put?

Yes. To change from I to we, you just change the subject prefix:

nitaweka – ni- (I) → I will put
tutaweka – tu- (we) → we will put

So the sentence would become:

Leo jioni, tutaweka vitabu vyetu kwenye meza.
(This evening, we will put our books on the table.)

Why is it vitabu vyetu and not vitabu wetu?

The possessive -etu (our) must agree with the noun class of the noun it modifies.

kitabu (book) is noun class 7.
vitabu (books) is its plural in noun class 8.

The possessive forms for -etu are:

chetu – our (class 7, for kitabu)
vyetu – our (class 8, for vitabu)

So:

kitabu chetu – our book
vitabu vyetu – our books

Wetu is the form used with noun class 1/2 (people), e.g.:

mtoto wetu – our child
watoto wetu – our children

Using vitabu wetu would break the agreement rule, so it’s incorrect.

Why does vyetu come after vitabu, instead of before like in English (our books)?

In Swahili, the noun usually comes first, and possessives/adjectives follow it:

vitabu vyetu – literally books our
mwalimu wetu – teacher our
nyumba yangu – house my

So the general pattern is:

Noun + Possessive
e.g. vitabu vyenu (your books), rafiki yangu (my friend)

How would I say our book (singular) instead of our books?

Change the noun and make the possessive agree with the singular class:

kitabu chetu – our book
(class 7 noun kitabu, class 7 possessive chetu)

So the whole sentence would be:

Leo jioni, mimi nitaweka kitabu chetu kwenye meza.
(This evening, I will put our book on the table.)

What exactly does kwenye mean here, and how is it different from juu ya?

Kwenye is a very common preposition meaning roughly in / at / on (a place). It marks a general location:

kwenye meza – at/on the table
kwenye nyumba – in/at the house
kwenye shule – at school

Juu ya means on top of, with a stronger sense of on the upper surface:

juu ya meza – on top of the table (emphasising the top surface)

In this sentence:

kwenye meza = on / at the table (quite neutral)
juu ya meza = explicitly on top of the table

Both can be used, but kwenye meza sounds a bit more general and very natural in everyday speech.

Could I say mezani instead of kwenye meza? What’s the difference?

Yes, you can say:

Leo jioni, mimi nitaweka vitabu vyetu mezani.

Here’s the difference:

kwenye meza – preposition + noun
mezani – noun + locative suffix -ni

Both mean roughly at/on the table, and in many contexts they are interchangeable.

Nuance:

mezani often sounds a bit more compact and is very common in spoken Swahili.
kwenye meza is slightly more explicit as a prepositional phrase.

For most learners, you can treat kwenye meza and mezani as near-equivalents: both are correct.

Can I move leo jioni to another position, like in English?

Yes, Swahili time expressions are fairly flexible. All of these are acceptable:

Leo jioni, mimi nitaweka vitabu vyetu kwenye meza.
Mimi nitaweka vitabu vyetu kwenye meza leo jioni.
Leo jioni nitaweka vitabu vyetu kwenye meza.

You usually don’t put it in the very middle of the verb phrase, so you’d avoid something unnatural like:

✗ Nitaweka leo jioni vitabu vyetu kwenye meza. (marked/awkward)

Common positions are at the beginning or at the end of the sentence.

Do I need both leo and jioni? Doesn’t jioni already mean evening?

jioni = evening (in general)
leo = today / this

Leo jioni = this evening (today evening), specific to today.

You could say just:

Jioni nitaweka vitabu vyetu kwenye meza.

This often means in the evening (later), and in context it usually refers to this evening, but leo jioni makes it very explicit that you mean this evening today, not evenings in general or on some other day.

Is the comma after Leo jioni required?

No. The comma is a matter of writing style, not grammar.

You can write:

Leo jioni, mimi nitaweka vitabu vyetu kwenye meza.
Leo jioni mimi nitaweka vitabu vyetu kwenye meza.

In speech, you would naturally pause a little after Leo jioni, and the comma just reflects that pause. Both written versions are fine.

Why is the future tense simply nitaweka and not something like nitakuwa nikiweka?

Swahili has:

A simple future with -ta-:
- nitaweka – I will put
A progressive/continuous future using kuwa
- -ki-:
- nitakuwa nikiweka – I will be putting / I will be in the process of putting

In your sentence, an ordinary future action is meant, so the simple form nitaweka is the natural choice.
You’d use nitakuwa nikiweka if you want to focus on the ongoing nature of the action at some future time, which is more advanced and less common for basic statements like this.