Learn Hardcore Esperanto: Hodiaŭ vespere mi volas promeni kun amikoj en la parko. - This evening I want to walk with friends in the park.

Hodiaŭ – sometime today (morning, afternoon, or evening).
Vespere – in the evening (could be today, tomorrow, etc., depending on context).
Hodiaŭ vespere – this evening today → clearly this evening (of today).

You could say only hodiaŭ or only vespere if context makes the rest obvious, but using both is natural when you want to be precise: “this evening (today)”.

What is the difference between “vespero” and “vespere”?

This is about word endings:

vesper‑o = vespero → a noun: evening
vesper‑e = vespere → an adverb: in the evening, during the evening, of an evening

In Esperanto, -e is the normal adverb ending. It often corresponds to English “in/at X” when talking about times of day:

mateno → matene = in the morning
tagmezo → tagmeze = at noon
nokto → nokte = at night
vespero → vespere = in the evening

In the sentence, vespere modifies the whole action (“want to walk”) and therefore needs the adverb form, not the noun form.

Is the word order “Hodiaŭ vespere mi volas promeni…” fixed, or can I move things around?

Word order in Esperanto is fairly flexible, because grammar is mostly shown by endings, not position.

All of these are grammatically correct and would normally mean the same:

Hodiaŭ vespere mi volas promeni kun amikoj en la parko.
Mi hodiaŭ vespere volas promeni kun amikoj en la parko.
Mi volas hodiaŭ vespere promeni kun amikoj en la parko.

The most neutral and common is usually: [time] + [subject] + [verb] + [rest], so your original sentence feels very natural.

You can move adverbs like hodiaŭ vespere or prepositional phrases like kun amikoj a bit for emphasis or style, but you shouldn’t split endings off words or change them.

Why do we say “mi volas promeni” with two verbs, and how does that work in Esperanto?

In Esperanto, volas is a normal present‑tense verb (I want), and promeni is an infinitive (to walk, to take a walk).

vol‑as = (I) want (root vol
- present ending -as)
promen‑i = promeni = to walk (for pleasure) (root promen
- infinitive ending -i)

Structure:

mi volas promeni = I want to walk

This is exactly how many verb + infinitive combinations work in Esperanto:

mi ŝatas legi = I like to read
ili devas lerni = they must learn
ni provas paroli = we try to speak

No extra word like English “to” or “that” is used; the -i ending already shows “to [verb]”.

Could the sentence be “Mi volas promeni hodiaŭ vespere kun amikoj en la parko” instead? Is that still correct?

Yes, that is fully correct.

Hodiaŭ vespere mi volas promeni kun amikoj en la parko.
Mi volas promeni hodiaŭ vespere kun amikoj en la parko.

Both are natural. The first puts the time first (slight emphasis on when). The second begins with the subject and wanting, which is also very typical.

In everyday Esperanto, both word orders occur; context and rhythm of the sentence often decide which sounds better to a speaker, but grammatically they’re equivalent.

Why is there no word for “to” before “promeni”, like English “I want *to walk”*?

Esperanto doesn’t need a separate word like English “to” before infinitives.

The infinitive is made by adding -i to the verb root:

iri = to go
manĝi = to eat
paroli = to speak
promeni = to walk (for pleasure)

So mi volas promeni is literally I want walk‑to, where -i already carries the “to” idea.

You never write “mi volas *al promeni”* or something similar; the infinitive alone is enough.

Why is there no “my” in “kun amikoj”? Shouldn’t it be “kun miaj amikoj”?

Both kun amikoj and kun miaj amikoj are possible; they just express different nuances:

kun amikoj = with friends (some friends, not specified whose; often naturally understood as “my friends” from context)
kun miaj amikoj = with my friends (explicitly says they are mine)

Esperanto does not automatically include “my” inside amikoj, but often you don’t need to say it if context is clear. If it matters whose friends they are, use:

kun miaj amikoj = with my friends
kun viaj amikoj = with your friends
kun siaj amikoj = with his/her/their own friends (reflexive)

Why doesn’t “amikoj” have -n (accusative) at the end?

The -n ending (accusative) is used mainly for:

Direct objects (the thing directly affected by the verb):
- Mi vidas la amikojn. = I see the friends.
  → amikojn has -n because it is what I see.
Showing direction of movement without a preposition:
- Mi iras hejmen. = I go home. (toward home)

In “Hodiaŭ vespere mi volas promeni kun amikoj en la parko”:

The main action is volas promeni.
There is no direct object of “want” or “walk”:
you don’t “want something” explicitly, and you don’t “walk something”.
kun amikoj = with friends; the preposition kun already shows the relationship, so amikoj stays in the basic nominative form (no -n).

Therefore amikoj correctly has no accusative -n here.

Why do we say “en la parko” and not just “la parko” or “parke”?

Each option has a slightly different structure:

en la parko
- en = in
- la parko = the park
  → in the park (location, very literal and common)
parke
- park‑e = in/at the park (adverb).
  You could say:
- …promeni kun amikoj parke.
  This is also correct and a bit more compact or stylistic.
Just la parko without a preposition would normally be a subject or object, not a place description, so it doesn’t fit here.

In normal speech, en la parko is probably the most straightforward and beginner‑friendly way; parke is more compact but slightly less transparent for beginners.

Why do we use the article “la” in “en la parko”, but not in “kun amikoj”?

The definite article la in Esperanto works similarly to English “the”:

la parko = the park (some specific park known from context)
parko = a park (some park, not specified)

For “amikoj”:

amikoj = friends or some friends (plural, indefinite)
la amikoj = the friends (some particular group of friends already known or defined)

The original sentence:

kun amikoj → with (some) friends (no need to specify which ones)
en la parko → in the park (some specific park we assume you have in mind)

You could say kun la amikoj if you mean a particular, previously mentioned group of friends. You could also drop la and say en parko if you mean “in some park or other,” but that sounds less specific.

Why is “volas” in the present tense if the action will happen in the future (this evening)?

In Esperanto, it’s normal to use present tense for wishes, plans, and intentions about the future when the time is made clear by another word:

Morgaŭ mi iras al la urbo. = Tomorrow I’m going to the city.
Poste ni manĝas. = Later we eat / we’ll eat.

Here:

Hodiaŭ vespere already shows that the walking will be in the future (later today).
mi volas = I want (right now)

So the sentence mainly says:

Right now I have the wish or intention that later this evening I will walk with friends in the park.

You could say “mi volos promeni” (I will want to walk), but that emphasizes that the wanting itself is in the future, which is usually not what you mean in everyday speech.

Can I omit the “mi” and just say “Hodiaŭ vespere volas promeni kun amikoj en la parko”?

No; in standard Esperanto you must include the subject pronoun mi.

Esperanto verbs do not change form to show the subject (there is no “am” vs “are” vs “is” difference), so without the pronoun, we usually don’t know who is doing the action:

volas promeni = want(s) to walk (who? I? you? they?)

You need:

Mi volas promeni… = I want to walk…
Vi volas promeni… = You want to walk…
Ili volas promeni… = They want to walk…

So in your sentence, mi is required.