Learn Hardcore Russian: Мне нравится приятный сон после долгого дня. - I like a pleasant sleep after a long day.

[Dative person] + нравится + [thing, nominative]
- Мне нравится сон. – I like sleep.
- Ему нравится музыка. – He likes music.
- Им нравятся фильмы. – They like films. (note plural verb)

What case is мне, and why is it used here?

Мне is the dative singular form of я (I).

You use the dative with нравиться to indicate “to whom” something is pleasing:

Я (nominative) → Мне (dative)

Examples:

Мне нравится сон. – Sleep is pleasing to me.
Тебе нравится музыка. – Music is pleasing to you.
Ей нравится кофе. – Coffee is pleasing to her.

In this sentence, мне marks the experiencer of the liking.

What is the grammatical role of приятный сон?

Приятный сон is the subject of the verb нравится.

Сон – noun, masculine singular, nominative.
Приятный – adjective, masculine singular, nominative, agreeing with сон.

Literal structure:

Мне (to me, dative)
нравится (is pleasing)
приятный сон (pleasant sleep – subject)

So grammatically it is “Pleasant sleep is pleasing to me.”

Why is it приятный сон and not приятное сон or приятная сон?

In Russian, adjectives must agree with the noun in:

gender
number
case

Here:

сон is masculine, singular, nominative.
So the adjective must also be masculine singular nominative: приятный.

Adjective endings in nominative singular:

Masculine: приятный (for сон)
Feminine: приятная (e.g. приятная музыка)
Neuter: приятное (e.g. приятное чувство)

So:

приятный сон – correct (masculine noun)
приятное сон – wrong (neuter adjective + masculine noun)
приятная сон – wrong (feminine adjective + masculine noun)

Why is it после долгого дня and not после долгий день?

The preposition после (“after”) always requires the genitive case.

Base phrase:

долгий день – “a long day”, nominative.

After после, both words must be in genitive singular:

долгий → долгого
день → дня

So:

после долгого дня – after a long day.

Using nominative (после долгий день) is simply ungrammatical in Russian.

What exactly are the forms долгого and дня? How are they formed?

They are both genitive singular forms.

долгий (long) → долгого
- Masculine / neuter adjective, genitive singular (also used for accusative animate, etc.).
- Pattern: -ий → -ого
  Examples:
  - новый → нового (new)
  - старый → старого (old)
  - долгий → долгого (long)
день (day) → дня
- Masculine noun, 2nd declension.
- Pattern: -ь → -я in genitive singular
  Examples:
  - конь → коня (horse)
  - гений → гения (genius)
  - день → дня (day)

So после долгого дня is “after a long day”, with both words correctly in genitive singular.

Can I say Я люблю приятный сон после долгого дня instead? What’s the difference?

You can say it, but the nuance is different.

Мне нравится приятный сон…
- Neutral, descriptive: “Pleasant sleep is (generally) pleasing to me.”
- Often used about tastes, preferences, current impressions.
Я люблю приятный сон…
- Stronger, more personal: “I love/ I really like pleasant sleep…”
- Sounds a bit more like a statement of attitude or character.

In everyday speech:

Мне нравится… is extremely common and slightly softer.
Я люблю… can feel stronger, more emotional or habitual, depending on context.

In this particular sentence, Мне нравится… sounds more natural and idiomatic.

Why isn’t there any word for “a” or “the” before приятный сон?

Russian has no articles (no a / an / the). Definiteness or indefiniteness is usually understood from context or word order.

приятный сон can mean:

“a pleasant sleep”
“the pleasant sleep”
“pleasant sleep” (in a general sense)

Which one you choose in English depends on the context, not on changes in the Russian phrase. In your sentence, translating it as “I like a pleasant sleep after a long day” or “I like having a pleasant sleep after a long day” would both be natural.

Could I say Мне нравится спать после долгого дня? How is that different from приятный сон?

Yes, you can say:

Мне нравится спать после долгого дня. – I like to sleep / I like sleeping after a long day.

Difference:

приятный сон – a noun phrase, focusing on the state/thing “pleasant sleep”.
спать – infinitive verb, focusing on the activity “to sleep”.

Subtle nuance:

Мне нравится приятный сон… – I enjoy the experience of a pleasant sleep (as an event/state).
Мне нравится спать… – I enjoy sleeping (the action) after a long day.

Both are correct; the original sounds a bit more stylistic or slightly more “poetic” because of the noun сон.

Why is the verb нравится (singular) and not нравятся?

The verb нравиться agrees with the thing that is liked (the subject in nominative).

Here, the subject is:

приятный сон – singular.

So you must use the singular form:

Мне нравится приятный сон.

If the thing liked were plural:

Мне нравятся приятные сны. – I like pleasant dreams.
(сны – plural → нравятся – plural verb)

Can I change the word order, for example: Приятный сон после долгого дня мне нравится?

Yes, Russian word order is relatively flexible. You can say:

Мне нравится приятный сон после долгого дня. – neutral; simple statement.
Приятный сон после долгого дня мне нравится. – puts more emphasis on приятный сон после долгого дня as the topic.

Both are grammatically correct. The first is more common in everyday speech and sounds more neutral. The second feels a bit more emphatic or contrastive, like “It’s pleasant sleep after a long day that I like.”

Is сон here singular in a specific sense (“one sleep”) or more general?

Grammatically, сон is singular, but Russian often uses the singular to talk about an activity in a general or repeated sense.

In context, приятный сон после долгого дня is more like:

“a pleasant sleep (whenever it happens) after a long day”
or even “pleasant sleep after a long day” as a general concept.

It doesn’t necessarily mean one specific occurrence; it can describe a general preference.

How would pronunciation and stress work for this sentence?

Stressed syllables (capitalized):

Мне – mnE (single syllable)
нра́вится – НРА-ви-тся → нрА-ви-тся
приятный – пр-и-ЯТ-ный → приЯТный
сон – SON (single syllable)
после – ПОС-ле → ПОс-ле (stress on first syllable)
долгого – ДОЛ-го-во → ДОл-го-во
дня – днЯ (single syllable, palatalized “dn”)

Approximate IPA:

Мне нравится приятный сон после долгого дня.
[mnʲe ˈnravʲɪt͡sə prʲɪˈjatnɨj son ˈposlʲe ˈdolɡəvə dnʲa]

The most important for learners is to stress:

нрА- in нравится
-ЯТ- in приятный
ДО- in долгого
-НЯ in дня

Are there other common adjectives I could use instead of приятный with сон?

Yes, very natural alternatives include:

крепкий сон – sound / deep sleep.
хороший сон – good sleep.
спокойный сон – calm, peaceful sleep.
долгий сон – long sleep.

Each slightly changes the nuance:

Мне нравится крепкий сон после долгого дня. – I like a good, deep sleep after a long day.
Мне нравится спокойный сон после долгого дня. – I like a peaceful sleep after a long day.

Grammatically, they behave the same way: masculine singular nominative adjective + сон.