Learn Hardcore Esperanto: En la arbaro la infanoj aŭskultas birdojn kaj serĉas belegajn florojn. - In the forest the children listen to birds and look for very beautiful flowers.

aŭskultas birdojn = listen to birds (birds are what they listen to)
serĉas belegajn florojn = look for beautiful flowers (flowers are what they look for)

Because the action is done to the birds and to the flowers, they take the accusative -n.

Why do birdojn and florojn have -j as well as -n?

The ending -j marks the plural (more than one), and -n marks the accusative.
When a noun is both plural and accusative, Esperanto combines them as -jn:

singular, subject: birdo (a bird)
plural, subject: birdoj (birds)
singular, object: birdon (a bird – object)
plural, object: birdojn (birds – object)

The same pattern applies to florojn.

Why is there la in en la arbaro, but no la before birdojn or belegajn florojn?

La is the definite article “the” in Esperanto, used when something is specific.

en la arbaro suggests a particular forest that is already known or defined.
birdojn and belegajn florojn are not marked as specific; they’re just “birds” and “beautiful flowers” in general.

Esperanto has no separate word for “a/an”. If there is no la, the noun can usually correspond to English “a/an” or just the bare plural (“birds”, “flowers”), depending on context.

Could I also say la birdojn or la belegajn florojn? Would that be wrong?

You can say la birdojn or la belegajn florojn, and it is grammatically correct, but it changes the meaning:

aŭskultas la birdojn = they listen to *the birds* (some specific birds)
serĉas la belegajn florojn = they look for *the beautiful flowers* (specific, known flowers)

Without la, it’s more like “(some) birds” and “(some) very beautiful flowers” in general.

What is the difference between aŭdi and aŭskulti? Why is it aŭskultas here?

aŭdi means “to hear” (sound reaches your ears, even passively).
aŭskulti means “to listen (to)” (you actively pay attention).

In la infanoj aŭskultas birdojn, the idea is that the children are actively listening to the birds, not just accidentally hearing them. That’s why aŭskultas is used.

Why is it aŭskultas birdojn instead of something like aŭskultas al la birdoj (“listen to the birds”)?

In Esperanto, aŭskulti takes a direct object with the accusative, so you say:

aŭskulti muzikon = to listen to music
aŭskulti la instruiston = to listen to the teacher
aŭskulti birdojn = to listen to birds

You don’t use a preposition like al or por here. The “to” in English “listen to” is built into the verb aŭskulti and shown by the accusative object.

Why is it serĉas belegajn florojn and not serĉas por belegaj floroj (“look for beautiful flowers”)?

The verb serĉi in Esperanto also takes a direct object:

serĉi laboron = to look for work
serĉi la ŝlosilon = to look for the key
serĉi belegajn florojn = to look for very beautiful flowers

You don’t need por or any other preposition; the thing you are searching for is just a direct object in the accusative.

What does belegajn mean exactly, and how is it formed?

Belegajn is the accusative plural form of belegaj, from the adjective belega.

bela = beautiful
bel‑eg‑a = very beautiful, gorgeous (-eg- is an intensifying suffix meaning “very big/strong”).

Then it agrees with florojn in number and case:

plural: belegaj floroj
accusative plural: belegajn florojn.

Why do belegajn and florojn both change endings? Isn’t it enough to mark just the noun?

In Esperanto, adjectives agree with the nouns they describe in both number and case.

Since florojn is plural and accusative, its adjective must also be plural and accusative:

singular, nominative: bela floro
plural, nominative: belaj floroj
singular, accusative: belan floron
plural, accusative: belajn florojn

The same pattern applies with belega → belegaj → belegajn.

Could the word order be La infanoj en la arbaro aŭskultas birdojn kaj serĉas belegajn florojn? Is that still correct?

Yes, that word order is also correct. Esperanto word order is relatively flexible.

En la arbaro la infanoj… puts more emphasis on “in the forest” at the start.
La infanoj en la arbaro… starts by emphasizing “the children” and then adds where they are.

Both sentences are grammatical and mean essentially the same thing; the difference is mainly in style and emphasis.

What exactly does arbaro mean, and how is it built?

Arbaro means “forest”. It’s built from smaller parts:

arbo = tree
-ar- = a collection or group of similar things
arbaro = a collection of trees → a forest

The ending -o marks it as a noun.

Why is it En la arbaro and not En arbaro?

Using la here makes the forest definite: en la arbaro = in the (particular) forest.

En arbaro would sound more like “in a forest / in forest” in a very general or abstract way (not a specific forest the speaker has in mind). In normal, concrete situations, if you’re talking about where the children actually are, en la arbaro is more natural.

How are aŭskultas and serĉas pronounced, especially aŭ and ĉ?

aŭ is a diphthong, roughly like English “ow” in “now”, but shorter and smoother.
ŭ is a semivowel like English w, but here it always forms part of the diphthong aŭ.
ĉ is pronounced like ch in “church”.

So roughly:

aŭskultas ≈ OW-skul-tas (with “OW” as in “now”)
serĉas ≈ SER-chas (rolled or tapped r, “ch” as in “church”).

Where is the stress in arbaro, aŭskultas, and belegajn?

In Esperanto, stress is always on the second‑to‑last syllable.

So:

ar‑BA‑ro (arBAro)
aŭ‑SKU‑ltas (aŭSKUltas)
be‑LE‑gajn (beLEgajn)

This rule is very regular and applies to almost all words.