Ni sidas ĉe unu flanko de la tablo, kaj la infanoj sidas ĉe la alia flanko.

Ĉe here means at or by in relation to a place: ĉe unu flanko de la tablo = at one side of the table.

It is not sur, because sur means on top of. If you said sur la tablo, that would mean on the table, not seated at it.

A learner might also think of apud, which means beside/next to. That can work in some contexts, but ĉe is very natural for being positioned at a table, door, wall, desk, and so on.

Sidas means are sitting. It tells you the people’s posture or position.

Estas would only mean are, which is less specific. Esperanto often uses posture verbs such as sidi (sit), stari (stand), and kuŝi (lie) more directly than English does.

So Ni sidas... is a natural way to say that we are seated on that side of the table.

This is the normal way to express one side ... the other side.

• unu flanko = one side
• la alia flanko = the other side

Here unu introduces one member of a pair, and la alia refers to the remaining one. It is a very common pattern in Esperanto.

In this sentence, alia means other.

Because the sentence already mentions one side, la alia flanko means the other side: the remaining side in the contrast.

Without context, alia can sometimes feel closer to another in English, but here the meaning is clearly the other.

De means of, from, or sometimes marks a relationship between nouns. Here it shows possession or connection:

• flanko de la tablo = side of the table

Esperanto does not have a special genitive ending for this. Instead, it commonly uses de where English uses of or an apostrophe structure.

There is no -n because there is:

1. no direct object, and
2. no movement toward a place

Sidi describes a state or location: people are already sitting somewhere. That is why ĉe unu flanko and ĉe la alia flanko stay as they are.

A beginner rule of thumb is:

• use -n for a direct object
• sometimes use -n for direction/motion

But this sentence is about location, not motion.

La means the.

• la infanoj = the children
• la tablo = the table

Those are specific.

But unu flanko means one side, where unu is the number one. Esperanto does not normally say la unu flanko here, because the point is the contrast one side / the other side.

Also, Esperanto has no separate indefinite article like English a/an. So there is no extra word corresponding to a in a side.

-j marks the plural.

• infano = child
• infanoj = children

This is one of the most important Esperanto endings:

• nouns usually end in -o
• plural nouns end in -oj

So la infanoj simply means the children.

Yes. You could say:

Ni sidas ĉe unu flanko de la tablo, kaj la infanoj ĉe la alia flanko.

That is still correct and understandable.

The repeated sidas just makes the sentence more explicit and balanced. Esperanto often allows this kind of omission when the meaning is already clear from the first clause.

Yes. Esperanto word order is fairly flexible, because the grammar is shown a lot by endings and function words rather than by rigid position.

For example, you could also say:

Ĉe unu flanko de la tablo ni sidas, kaj ĉe la alia flanko sidas la infanoj.

That is still grammatical. However, the original version is the most neutral and easiest for beginners to follow.

A few helpful points:

• ĉ sounds like ch in church
• j sounds like y in yes
• stress falls on the second-to-last syllable

A rough pronunciation guide is:

Ni SI-das ĉe U-nu FLAN-ko de la TA-blo, kaj la in-FA-noy SI-das ĉe la a-LI-a FLAN-ko.