En mia poŝo estas nur kelkaj moneroj.

Esperanto often allows flexible word order. Starting with En mia poŝo puts the location first for emphasis, like In my pocket, there are only a few coins.

The more neutral order would be:

• Nur kelkaj moneroj estas en mia poŝo.

But En mia poŝo estas... sounds very natural, especially when introducing what exists in a place. It works a lot like There are only a few coins in my pocket in English.

Because kelkaj moneroj is the subject of the sentence, not the direct object.

In Esperanto, the -n ending marks:

• a direct object
• or motion toward something in some cases

Here, the sentence is saying that a few coins are in the pocket. The coins are what exists, so they are the subject. That is why it stays:

• kelkaj moneroj

not:

• kelkajn monerojn

In Esperanto, esti does not change for number. The verb form is always the same:

• mi estas
• vi estas
• li estas
• ili estas

So even with a plural subject like kelkaj moneroj, you still use estas.

Both are possible, but they feel slightly different.

• En mia poŝo estas nur kelkaj moneroj.
  This presents the location first and then says what is there. It is very natural in existence-type sentences.

• Nur kelkaj moneroj estas en mia poŝo.
  This focuses more directly on only a few coins.

The version with estas before the subject is especially common after a place expression like en mia poŝo.

Kelkaj means a few or some in the sense of an unspecified small number.

So:

• kelkaj moneroj = a few coins

By contrast, iuj usually means some / certain ones, often with a vaguer or less quantity-focused meaning.

Compare:

• Mi havas kelkajn librojn. = I have a few books.
• Iuj libroj estas tre malnovaj. = Some books are very old.

In your sentence, kelkaj is the natural choice because the speaker is talking about a small number of coins.

Nur means only, and it usually goes right before the part it limits.

So:

• nur kelkaj moneroj = only a few coins

This shows that the limitation applies to the quantity of coins.

If you moved nur, the emphasis could change. Esperanto often uses word placement to show what only refers to.

Because mia is the possessive adjective form meaning my.

Esperanto correlates these forms clearly:

• mi = I
• mia = my
• la mia = mine

So:

• mia poŝo = my pocket

The -a ending shows that mia is an adjective, and adjectives modify nouns.

Because mia agrees with poŝo, and poŝo is singular and not accusative.

Esperanto adjectives match the noun they describe in:

• number
• accusative marking

Here:

• poŝo = singular
• not a direct object
• so mia stays just mia

If the noun changed, the adjective would change too:

• miaj poŝoj = my pockets
• mian poŝon = my pocket as a direct object

Esperanto usually does not need a dummy subject like English there.

English says:

• There are only a few coins in my pocket.

But Esperanto simply says:

• En mia poŝo estas nur kelkaj moneroj.

The language can state existence directly without adding a placeholder word. The location phrase plus estas is enough.

Esperanto uses la only when the noun is definite, meaning the listener is expected to know exactly which thing is meant.

Here, kelkaj moneroj means a few coins, not the few coins, so no article is used.

Compare:

• kelkaj moneroj = a few coins
• la moneroj = the coins

Since the sentence is just talking about an unspecified small number of coins, no la is needed.

Poŝo usually means pocket in the ordinary sense, especially a pocket in clothing or a bag.

So En mia poŝo naturally means in my pocket.

Depending on context, it can also be used in extended senses, but for learners it is best to think of it first as the normal everyday word pocket.

Ŝ is pronounced like English sh in shoe.

So poŝo is pronounced approximately:

• POH-sho

with the stress on the second-to-last syllable, because Esperanto stress normally falls on the penultimate syllable:

• PO-ŝo

Actually, since there are only two syllables, the stress is on PO.

So a better guide is:

• POH-sho, with stress on POH.

Yes, that is grammatically correct.

• Estas nur kelkaj moneroj en mia poŝo.

This keeps the same meaning. The difference is mainly emphasis and style.

• En mia poŝo estas nur kelkaj moneroj. puts the location first.
• Estas nur kelkaj moneroj en mia poŝo. starts more like an existence statement.
• Nur kelkaj moneroj estas en mia poŝo. focuses more on the small quantity.

All are possible, but the original sentence sounds very natural.