Li legas literaturon en la studio.

Because it is the direct object of the verb legas.

In Esperanto, direct objects usually take the ending -n:

• Li legas libron. = He reads a book.
• Li legas literaturon. = He reads literature.

So:

• literaturo = literature
• literaturon = literature, as the thing being read

Even though literature is often uncountable in English, Esperanto still marks it as a direct object with -n.

Esperanto verbs do not change according to the subject.

So:

• mi legas = I read
• vi legas = you read
• li legas = he reads
• ŝi legas = she reads
• ili legas = they read

The ending -as always means present tense.

That is much simpler than English, where we say I read but he reads.

La is the Esperanto definite article, meaning the.

So:

• studio = a studio / studio
• la studio = the studio

Esperanto has only one article, la, for all genders and numbers. It does not change:

• la libro = the book
• la libroj = the books

In this sentence, la studio refers to a specific studio.

Because en la studio shows location, not a direct object.

Compare:

• Li legas literaturon. → literaturon is the direct object, so it gets -n
• en la studio → this is a prepositional phrase meaning in the studio, so normally no -n

So here:

• en = in
• la studio = the studio

Together: en la studio = in the studio

Yes, but only if it shows movement toward a place rather than location in a place.

Compare:

• Li estas en la studio. = He is in the studio.
• Li iras en la studion. = He goes into the studio.

In your sentence, the person is already located there while reading, so en la studio is correct.

Yes. Esperanto word order is fairly flexible, because endings show the grammar clearly.

The neutral order is:

• Li legas literaturon en la studio.

But these are also possible, with different emphasis:

• En la studio li legas literaturon.
• Literaturon li legas en la studio.

Because literaturon has -n, we still know it is the object even if it moves in the sentence.

It can mean either, depending on context.

Esperanto present tense -as is broader than English:

• Li legas can mean he reads
• or he is reading

If the context does not make the timing more specific, both are possible.

In Esperanto, nouns normally have a basic singular form ending in -o:

• libro = book
• literaturo = literature

If you want plural, you add -j:

• libroj = books

But literaturo is usually treated as a general mass noun, like literature in English, so singular is normal here.

Here is the breakdown:

• Li = pronoun, he
• legas = verb, present tense of legi (to read)
• literaturon = noun, direct object form of literaturo
• en = preposition, in
• la = definite article, the
• studio = noun, studio

This is a very typical Esperanto sentence pattern: subject + verb + object + prepositional phrase

Esperanto pronunciation is very regular. A rough English-style guide is:

lee LEH-gahs lee-teh-rah-TOO-ron en lah STOO-dee-oh

A few helpful points:

• li sounds like lee
• e is always like e in met, not like English ee
• g is always hard, as in go
• u sounds like oo
• Stress is always on the second-to-last syllable:
  • leGAs
  • literaturaTUron
  • STUdio

Usually you would say en la studio if you mean in the studio.

Leaving out la would make it less definite and often less natural in a sentence like this. Esperanto does not have an indefinite article like a/an, so:

• studio can mean a studio or just studio in a general sense
• la studio means the studio, a specific one

So in this sentence, en la studio is the expected form.