Learn Hardcore Russian: Этот гид работает во дворце днём, а вечером водит туристов по набережной. - This guide works in the palace in the daytime and in the evening leads tourists along the embankment.

before some words starting with two consonants (especially when the first is в or ф) to make pronunciation easier:
- во Франции, во втором ряду, во флоте
sometimes just by tradition / euphony, even if в is technically possible.

With дворец the standard, natural form is во дворце.
в дворце is not wrong grammatically, but it sounds awkward and is almost never used in normal speech.

What case is во дворце, and why do we use that case here?

во дворце is in the prepositional case (singular).

The verb работать answers the question где? (where?) when talking about place of work, so it takes a preposition of location (в, на) + prepositional case:

работать в школе
работать в офисе
работать на заводе
работать во дворце

So дворец → во дворце (prepositional) means in the palace as a location.

What form is днём, and why not just день?

днём is the instrumental singular form of день.

Russian often uses the instrumental case of time‑of‑day nouns as an adverb of time:

утро → утром = in the morning
день → днём = in the daytime / during the day
вечер → вечером = in the evening
ночь → ночью = at night

So днём here means during the day / in the daytime, not the noun day itself. You don’t need a preposition like in; the case ending alone gives that meaning.

Does днём mean specifically “afternoon” or any time during the day?

днём generally means in the daytime, i.e. when it’s light outside – roughly from late morning through late afternoon.

It doesn’t sharply distinguish between late morning and afternoon. In this sentence, the important point is just the contrast:

днём = during the day
вечером = in the evening

So you should understand it as “in the daytime” rather than a precise “afternoon”.

Why is it а вечером, not и вечером?

Both а and и can be translated as and, but:

и just adds another item: X and Y
а usually expresses contrast or a different situation: X, while/whereas Y

Here the sentence contrasts what happens at different times:

днём he works in the palace,
а вечером (whereas in the evening) he leads tourists along the embankment.

So а is better because it highlights the contrast between daytime and evening activities.

Why is вечером also in the instrumental case?

вечером is the instrumental singular of вечер, used in exactly the same adverbial way as днём:

вечером = in the evening

This is a standard pattern for times of day:

утром, днём, вечером, ночью

So а вечером = and in the evening / whereas in the evening.

Why is it водит туристов and not ведёт туристов?

Both verbs come from the motion verb pair вести / водить:

вести – unidirectional (one specific movement in one direction)
водить – multidirectional / repeated / habitual motion

We use водить when:

the action is habitual or part of someone’s job,
or involves movement here and there, possibly in multiple directions.

In this sentence, we’re describing his regular work routine in the evenings, so Russian prefers водит туристов:

По вечерам он водит туристов по набережной.
(He leads tourists along the embankment in the evenings – as a regular activity.)

If you said ведёт туристов, it would sound more like describing one specific occasion right now:

Сейчас он ведёт туристов по набережной.
(Right now he is leading tourists along the embankment.)

Why is it туристов and not туристы?

туристы is nominative plural (subject form): туристы идут – the tourists are going.

Here, туристов is the direct object of водит: he is leading whom? – туристов.

For animate masculine plural nouns, the accusative plural is identical to the genitive plural:

Nominative plural: туристы
Genitive plural: туристов
Accusative plural (animate): also туристов

So водит кого? туристов – accusative plural (animate).

Why do we say по набережной and not на набережной?

The preposition по with the dative case often means along / over / around a surface or area.

идти по улице – to walk along the street
гулять по парку – to stroll around the park
ходить по берегу – to walk along the shore

So водит туристов по набережной = leads tourists along the embankment (they are moving along it).

на набережной (with prepositional) would usually describe location (“on the embankment”) rather than movement along it:

Мы стоим на набережной. – We are standing on the embankment.

Here the focus is on motion along a route, so по набережной is the natural choice.

What case is набережной here, and how is it formed?

набережной here is dative singular of набережная (a feminine noun ending in -ая).

Nominative singular: набережная
Dative singular: набережной

The preposition по can take dative when it means “along / over”:

по дороге, по улице, по реке, по набережной

So по набережной = along the embankment (preposition по + dative singular).

Why is it Этот гид, and not a feminine form, if the guide is a woman?

The noun гид is grammatically masculine in Russian.

In practice:

For a male guide: Этот гид – clearly masculine.
For a female guide: people usually still say этот гид, because the noun itself is masculine.

There is a feminine form гидесса, but it’s rare and sounds informal or old-fashioned. More natural options are:

женщина‑гид
or just use гид and make it clear from context that it’s a woman.

Grammatically, гид behaves as a masculine noun, so demonstratives and adjectives normally agree in masculine: этот гид, хороший гид.

Why is there a comma before а in this sentence?

Russian puts a comma before coordinating conjunctions like а, и, но when they join two independent clauses (two parts that could be sentences on their own):

Этот гид работает во дворце днём,
а вечером водит туристов по набережной.

Each part has its own subject and verb:

Этот гид работает...
(Он) водит туристов... (subject understood from context)

Therefore, this is a compound sentence, and Russian punctuation requires a comma before а.

What tense/aspect are работает and водит? Are they like “is working / is leading”?

Both работает and водит are present tense, imperfective aspect.

In Russian, the present imperfective covers:

current ongoing actions (is working right now), and
regular / habitual actions (works (every day)).

Here, because we have днём / вечером, the sentence describes a regular routine:

Он днём работает во дворце, а вечером водит туристов...
= He works in the palace during the day and (regularly) leads tourists along the embankment in the evening.

Russian doesn’t distinguish he works vs he is working morphologically; both are just он работает / он водит.