La patrino diras, ke lerta infano jam scias zorgi pri sia ĉambro.

Ke means that and introduces a subordinate clause.

So the sentence is structured like this:

• La patrino diras = The mother says
• ke ... = that ...
• lerta infano jam scias zorgi pri sia ĉambro = a clever child already knows how to take care of his/her room

Esperanto uses ke very regularly for this kind of that-clause.

In Esperanto, a subordinate clause introduced by words like ke is normally separated by a comma.

So:

• La patrino diras, ke ...

This is more regular than in English, where that is sometimes written without a comma.

La means the.

• la patrino = the mother, a specific mother
• lerta infano = a clever child or clever children/child in general, depending on context

Without la, infano is indefinite or generic. The sentence is not talking about one specifically identified child, but about a clever child as a type or as an unspecified child.

If you said la lerta infano, that would mean the clever child, referring to a particular child already known in the context.

In Esperanto, adjectives always end in -a.

So:

• lerta = clever, skillful
• bona = good
• granda = big

Because lerta describes infano, it takes the adjective ending -a.

Also, Esperanto adjectives usually match the noun in number and accusative marking. Here both are singular and not accusative, so:

• lerta infano

If it were plural, it would be:

• lertaj infanoj

Lerta often means clever, skillful, capable, or good at doing things efficiently.

It does not only mean intellectually smart. It often suggests practical competence too. In this sentence, it implies that a child who is capable or sensible already knows how to manage their room.

So lerta infano can suggest something like:

• a clever child
• a capable child
• a skillful child

The best English translation depends on context.

Jam usually means already.

Here:

• jam scias = already knows

It shows that this knowledge or ability has been achieved by now.

Esperanto word order is fairly flexible, but jam is commonly placed before the word it modifies most directly. In this sentence, it naturally modifies scias.

In Esperanto, scii can be followed directly by an infinitive to mean know how to do something.

So:

• scias zorgi = knows how to take care

This is very normal Esperanto.

You can also say:

• scias kiel zorgi = knows how to take care / knows how one should take care

But scias zorgi is shorter and very natural.

Compare:

• Mi scias naĝi = I know how to swim
• Ŝi scias kuiri = She knows how to cook

Because zorgi is normally used with the preposition pri when it means to take care of or to be concerned about.

So:

• zorgi pri infano = take care of a child
• zorgi pri la domo = take care of the house
• zorgi pri sia ĉambro = take care of one’s room

This is something you simply learn as part of the verb’s pattern: zorgi pri.

English says take care of, while Esperanto says zorgi pri.

Sia is the reflexive possessive adjective. It refers back to the subject of the clause it is in.

In the subordinate clause, the subject is:

• lerta infano

So:

• sia ĉambro = that child’s own room

This shows that the room belongs to the child, not to someone else.

If you used lia or ŝia, that would point to some other male or female person mentioned in the context, not automatically back to infano.

This is a very important Esperanto rule:

• sia = one’s own, referring back to the subject of the same clause

It refers to lerta infano, not la patrino.

That is because sia refers to the subject of its own clause.

There are two clauses here:

1. La patrino diras
2. ke lerta infano jam scias zorgi pri sia ĉambro

Inside the ke-clause, the subject is lerta infano, so sia refers to that child.

It does not refer back across the clause boundary to la patrino.

The -n ending marks the direct object in Esperanto.

In this sentence:

• infano is not a direct object; it is the subject of the subordinate clause
• ĉambro is not a direct object either, because it comes after the preposition pri

After a preposition like pri, nouns normally do not take -n.

So:

• lerta infano = subject
• pri sia ĉambro = prepositional phrase

That is why neither noun has -n here.

Both are in the present tense because they end in -as.

Esperanto verb endings are very regular:

• -as = present
• -is = past
• -os = future
• -us = conditional
• -u = imperative/jussive
• -i = infinitive

So:

• diras = says / is saying
• scias = knows / knows how

The ending -i marks the infinitive, the basic verb form.

So:

• zorgi = to take care

In this sentence, zorgi depends on scias:

• scias zorgi = knows how to take care

This is similar to English structures like:

• knows how to swim
• knows how to cook

So zorgi is not the main finite verb of the clause; it is an infinitive complement.

Esperanto word order is fairly flexible, but this sentence uses a very normal and clear order.

Standard order here is:

• La patrino diras, ke lerta infano jam scias zorgi pri sia ĉambro.

Some parts could be moved for emphasis, but not every rearrangement sounds equally natural. For learners, the safest choice is to keep this straightforward order:

• subject + verb
• ke
  • subject + adverbs + verb + infinitive phrase

So yes, Esperanto allows flexibility, but this sentence is already in a very natural form.