Learn Hardcore Russian: Я люблю гулять по парку вечером. - I like to walk around the park in the evening.

The infinitive (гулять) expresses the action in a general, abstract way, not at a specific time. So я люблю гуляю would be wrong here; you must use the infinitive: я люблю гулять.

What is the difference between я люблю гулять and мне нравится гулять?

Both can be translated as I like to walk, but there is a nuance:

Я люблю гулять.
- Literally: I love to walk.
- Sounds a bit stronger, more personal, often used when it’s a regular habit or something important to you.
Мне нравится гулять.
- Literally: Walking is pleasing to me.
- Often a bit more neutral, like I enjoy walking / I like walking.

In everyday speech, they often overlap, and both are correct in this sentence. The original Я люблю гулять по парку вечером emphasizes more of a personal fondness for this habit.

What exactly does гулять mean? Is it just “to walk”?

Гулять is broader than just to walk:

To walk / to stroll for pleasure:
- Я люблю гулять по парку. – I like to stroll in the park.
To be out / hang out outside:
- Дети гуляют во дворе. – The kids are playing / hanging out in the yard.
To walk (a dog):
- Я гуляю с собакой. – I’m walking the dog.

It usually implies an unhurried, leisurely activity, not purposeful fast walking like exercise walking. For “to go somewhere on foot” as a mode of transport, Russians often use идти пешком (to go on foot):
Я иду в школу пешком. – I walk to school.

Why is it по парку and not в парке?

Both are possible, but they focus on different aspects:

гулять в парке – to walk in the park (you are located inside the park; neutral location)
гулять по парку – to walk around the park / through the park (movement around/within the space)

По + dative (here: по парку) often suggests movement over an area: along, around, through it. So гулять по парку paints a picture of moving around inside the park, not just being there.

Why is парк changed to парку? What case is that?

Парк becomes парку because of the preposition по, which in this meaning (movement around a place) requires the dative case.

Nominative (dictionary form): парк
Dative singular: парку

Pattern (masculine, hard consonant):

парк → парку
город → городу
лес → лесу

So по парку literally means along/around the park and grammatically is по + dative.

What does по mean here, and is it always used with the dative?

In this sentence, по expresses movement within an area: along, around, through.

Yes, in this meaning it takes the dative case:

гулять по парку – to walk around the park
ходить по городу – to walk around the city
бегать по пляжу – to run along the beach

По can have other meanings and use other cases in different contexts, but with the meaning around/along/over (a place), it uses the dative.

Why is there no preposition before вечером? Why not в вечером?

Words for parts of the day often use the instrumental case without a preposition to say in/at [that time of day]:

утром – in the morning
днём – in the daytime / in the afternoon
вечером – in the evening
ночью – at night

So вечер (evening) → вечером (instrumental) means in the evening by itself.
В вечером is incorrect; the preposition в is not used here.

Can I change the word order, for example: Вечером я люблю гулять по парку?

Yes. Russian word order is fairly flexible. All these are correct and natural; they just change emphasis slightly:

Я люблю гулять по парку вечером.
Neutral; slight focus on in the evening as an extra detail.
Вечером я люблю гулять по парку.
Emphasis on in the evening (as opposed to other times).
Я вечером люблю гулять по парку.
Focus on evenings as your usual time.

The core meaning remains the same: you enjoy walking in the park in the evenings.

What aspect is гулять, and could I say я люблю погулять?

Гулять is imperfective (ongoing, habitual, repeated action).

Using любить with the infinitive imperfective is the normal way to talk about general likes:

Я люблю гулять.
Я люблю читать.

Погулять is perfective (a completed action, to have a walk).
Я люблю погулять is possible colloquially and can sound like:

I like to have a (good) walk from time to time / every now and then.

It often implies doing it as a complete, satisfying activity. But if you’re a learner, stick first with я люблю гулять, which is the standard neutral form.

How is the whole sentence pronounced, and where is the stress?

Stresses (capital letters show the stressed syllable):

Я люблю гуля́ть по па́рку вéчерoм.

Roughly in IPA:

/ja lʲʊˈblʲu ɡʊˈlʲatʲ pɐ ˈparkʊ ˈvʲet͡ɕɪrəm/

Notes:

лю in люблю is like lyu (soft л).
гулять ends with a soft ть [tʲ].
вечером has stress on the first syllable: вé-че-ром.

How does люблю conjugate with other persons?

Люблю is 1st person singular of любить (to love/like):

я люблю – I love / like
ты любишь – you (sg., informal) love / like
он / она / оно любит – he / she / it loves / likes
мы любим – we love / like
вы любите – you (pl. or formal) love / like
они любят – they love / like

For example:

Мы любим гулять по парку вечером. – We like walking in the park in the evening.

Could I say по паркам instead of по парку? What would change?

Yes, but it changes the meaning:

по парку – around the park (one specific park)
по паркам – around (various) parks (plural)

Grammatically:

Singular dative: парк → парку
Plural dative: парки → паркам

So Я люблю гулять по паркам вечером would mean I like walking around parks in the evening (not tied to one particular park).