Мы молча шли по аллее, потому что после долгого дня хотелось тишины.

Молча is an adverb meaning silently, without speaking, or in silence.

It describes how they were walking:

• Мы шли = we were walking
• Мы молча шли = we were walking silently

A learner might expect something like an adjective, but Russian uses the adverb молча very naturally in this kind of sentence.

Russian distinguishes between two common verbs for to go/walk on foot:

• идти / шёл, шли = to be going, moving in one direction, at a particular time
• ходить / ходил, ходили = to go habitually, repeatedly, or in more than one direction

Here, the sentence describes one ongoing movement along the alley at that moment, so шли is the right choice.

• Мы молча шли по аллее = We were walking silently along the alley.
• Мы молча ходили по аллее would sound more like we used to walk around there, or walked back and forth.

Russian past tense agrees with the subject in number and, in the singular, gender:

• я шёл / я шла
• он шёл
• она шла
• мы шли
• они шли

Since the subject is мы (we), the verb must be plural: шли.

Here по means along or down, and with that meaning it takes the dative case.

• dictionary form: аллея
• dative singular: аллее

So:

• по аллее = along the alley

This is a very common pattern:

• идти по улице = to walk along the street
• гулять по парку = to walk around the park
• ехать по дороге = to go along the road

In this sentence, the best meaning is along the alley or down the alley.

Russian по often focuses on movement along a surface, path, or route. English sometimes translates this in different ways depending on context:

• along the alley
• down the alley
• sometimes even through the alley

But grammatically, Russian is using the normal pattern по + dative for movement along a path.

Because потому что introduces a subordinate clause meaning because.

Russian normally puts a comma before subordinate clauses:

• Мы молча шли по аллее, потому что...

So the comma works much like in English:

• We walked silently along the alley, because...

The preposition после (after) takes the genitive case.

So:

• день = day
• дня = genitive singular
• долгий день = a long day
• долгого дня = of a long day / after a long day

That gives:

• после долгого дня = after a long day

Both the adjective and noun go into the genitive:

• долгого matches дня

This is a very important Russian pattern.

Хотелось comes from хотеться, an impersonal verb meaning something like:

• to feel like
• to want
• to be in the mood for

So хотелось тишины is more like:

• there was a desire for silence
• one wanted silence
• silence was what was wanted

By contrast, хотели would come from хотеть, the personal verb to want, as in:

• мы хотели тишину / тишины is not the normal way here
• more natural would be мы хотели тишины only in certain contexts, but нам хотелось тишины is much more idiomatic for a feeling or mood

So хотелось makes the sentence sound natural and emotional: after a long day, there was a desire for quiet.

Yes, нам хотелось тишины would also be correct, and it may even be the version many learners expect first.

Russian often uses:

• мне хотелось = I wanted / I felt like
• нам хотелось = we wanted / we felt like

But in this sentence, нам is omitted because it is already easy to understand from the context that the feeling belongs to we.

So:

• ...потому что после долгого дня хотелось тишины = because after a long day, silence was what one wanted / we wanted quiet
• ...потому что после долгого дня нам хотелось тишины = a more explicit version

The version without нам can sound a bit more literary or smooth.

Because хотеться normally takes the thing desired in the genitive case.

So:

• тишина = silence, quiet
• тишины = genitive singular

Compare:

• Я хочу тишину — possible in some contexts, but not the most natural everyday phrasing
• Я хочу тишины — I want some quiet / I want silence
• Мне хочется тишины — I feel like I need some quiet

With хотеться, the genitive is especially common and natural.

It often gives the sense of wanting some amount of something, especially abstract things like:

• тишины = silence / quiet
• покоя = peace
• отдыха = rest

Тишина can mean:

• silence
• quiet
• peace and quiet

In this sentence, тишины probably does not mean total absolute silence in a strict sense. It more likely means they wanted calm, quiet, and no conversation or noise after a long day.

So in natural English, depending on style, you might translate it as:

• silence
• quiet
• some peace and quiet

Russian word order is flexible, but different orders change emphasis.

The sentence starts with:

• Мы = we
• молча = silently
• шли = were walking
• по аллее = along the alley

This order sounds neutral and natural: first the subject, then the manner, then the action, then the path.

Other orders are possible:

• Молча мы шли по аллее = emphasizes silently
• По аллее мы шли молча = emphasizes the setting/path
• Мы шли по аллее молча = also natural

So the chosen order is just a smooth, standard narrative order.

Yes, шли already shows a plural subject, so Russian can often omit мы if the context is clear.

For example:

• Молча шли по аллее... could work in context.

But Russian often includes the pronoun when it helps the sentence feel clearer or more balanced. Here мы is perfectly natural and gives the sentence a clear starting point.

So both are possible, but:

• Мы молча шли по аллее... = explicit, clear, natural
• Молча шли по аллее... = more context-dependent, more literary/narrative

It describes an ongoing scene in the past.

The verb шли is past tense of an imperfective verb (идти), so it presents the action as in progress:

• they were walking
• the scene is being described as it unfolded

That fits well with the atmosphere of the sentence: a quiet moment after a long day.

If Russian wanted to focus on arrival or completion, it would usually use a different verb or structure. Here the point is the process and mood, not the endpoint.