Se mi havos tempon en aŭgusto, mi vizitos amikinon, kiu laboras en librovendejo apud la stacidomo.

This is a very common question. Esperanto usually uses the tense that matches the actual time being talked about.

So in Se mi havos tempon..., the having of time is in the future, so havos is natural.

• se = if
• havos = will have

English is different here: after if, English usually uses present tense for future meaning. Esperanto does not have to do that.

So:

• Se mi havos tempon... = If I have/will have time...
• Mi vizitos... = I will visit...

Both actions are future, so both verbs can be future.

The -n marks the direct object, called the accusative.

Here, the person being visited is the direct object of vizitos, so Esperanto adds -n:

• mi vizitos amikinon = I will visit a female friend

Without -n, amikino would be the subject or just a plain noun form. With -n, Esperanto clearly shows that she is the one receiving the action.

This is one reason Esperanto word order is fairly flexible: the -n helps show who is doing what.

Because kiu is the subject of the relative clause kiu laboras en librovendejo.

A very important rule is this: the case of the relative pronoun depends on its role in its own clause, not on the form of the noun it refers to.

So:

• amikinon is accusative in the main clause because it is the object of vizitos
• kiu is nominative in the relative clause because it is the subject of laboras

If the relative pronoun were the object inside its clause, then it would be kiun.

The suffix -in- marks female sex.

So:

• amiko = friend
• amikino = female friend

Then amikinon is just the accusative form of amikino.

So the structure is:

• amik- = friend
• -in- = female
• -o = noun ending
• -n = accusative

For the same reason: it is the direct object of havos.

• mi havos tempon = I will have time

Even though time is abstract, Esperanto still treats it as a normal direct object after havi.

So in this sentence there are two accusatives:

• tempon after havos
• amikinon after vizitos

Because the sentence describes the friend as someone who currently works there, or generally works there.

The relative clause is identifying her:

• amikinon, kiu laboras en librovendejo...
• a female friend who works in a bookstore...

Even though the visit is in the future, her job is presented as a present fact about her.

If you said kiu laboros, that would mean who will work, which shifts the meaning and puts the working itself specifically in the future.

It is a compound word, and Esperanto loves compounds.

Break it down like this:

• libro = book
• vend- = sell
• -ej- = place
• -o = noun

So librovendejo literally means a place for selling books.

In normal English, that is a bookstore or bookshop.

Not quite.

• apud = beside, next to, by
• ĉe = at, with, at the place of

So apud la stacidomo means the bookstore is next to the station.

If you used ĉe, the meaning would be less specifically physical. Apud gives a clearer sense of nearby position.

Stacidomo is the usual Esperanto word for a railway station or train station.

It can be understood as a built-up word meaning something like station building.

So:

• apud la stacidomo = next to the train station

Learners sometimes expect stacio, but stacidomo is very common for the railway station.

Yes, Esperanto can express time in more than one way.

In this sentence, en aŭgusto simply means in August.

That is a very natural and straightforward choice.

You may also see a bare accusative of time, such as aŭguston, which can also mean in August or during August. But en aŭgusto is often easier for learners and very common.

So:

• en aŭgusto = in August
• aŭguston = in August / during August

Both are possible, but en aŭgusto is especially transparent.

In Esperanto, subordinate clauses are normally separated by commas.

That includes clauses introduced by words like:

• se = if
• ke = that
• kiu = who/which/that

So the comma before kiu is standard punctuation marking the start of the relative clause:

• mi vizitos amikinon, kiu laboras...

English is less consistent about this, especially with restrictive relative clauses, but Esperanto commonly uses the comma here.

Yes. In Esperanto, kiu can refer to a person or a thing, depending on context.

So here:

• amikinon, kiu laboras... = a female friend who works...

English separates these ideas into who and which, but Esperanto uses kiu much more broadly.

That is completely normal.

In Esperanto, month names are normally not capitalized unless they begin a sentence.

So:

• aŭgusto
• septembro
• januaro

That is standard Esperanto style.

As for pronunciation, aŭ is a diphthong. The ŭ is a very short w-like sound. In aŭgusto, aŭ sounds roughly like the ow in now, though not exactly identical for every speaker.

So aŭgusto is approximately:

• ow-GOOS-to

with Esperanto-style vowels and stress.

The given word order is the most natural and easy to understand, but Esperanto word order is more flexible than English because of endings like -n.

For example, the -n on amikinon shows it is the object, so Esperanto does not depend as heavily on word order to show grammatical roles.

Still, this sentence is written in a very standard, clear order:

• condition first: Se mi havos tempon en aŭgusto
• main action next: mi vizitos amikinon
• extra description last: kiu laboras en librovendejo apud la stacidomo

That is exactly the kind of order learners should aim for.