Lad være med at drikke kaffe om aftenen, hvis du vil gå i seng tidligt.

Lad være med at is a very common Danish way to say don’t do something.

So:

• Lad være med at drikke kaffe = Don’t drink coffee

Literally, it is something like leave off from doing or refrain from doing, but in normal English the best translation is simply don’t.

It is especially common in spoken and everyday Danish, and learners will see it a lot.

After lad være med, Danish normally uses at + infinitive.

So the pattern is:

• lad være med at + verb

Examples:

• Lad være med at ryge. = Don’t smoke.
• Lad være med at larme. = Don’t make noise.

Here:

• drikke = to drink
• at drikke = to drink

So at is there because drikke is in the infinitive after this expression.

Yes. Drik ikke kaffe om aftenen is also correct and means the same basic thing.

The difference is mostly in style and tone:

• Drik ikke kaffe om aftenen = a more direct negative command
• Lad være med at drikke kaffe om aftenen = often sounds a little more natural, conversational, or less abrupt

Danish very often prefers lad være med at for negative imperatives, especially in everyday speech.

Om aftenen means in the evening(s) or in the evening depending on context.

In this sentence, it means something like:

• in the evening
• during the evening

The phrase is built like this:

• om = in/during
• aftenen = the evening

Danish often uses om with parts of the day in general time expressions:

• om morgenen = in the morning
• om eftermiddagen = in the afternoon
• om aftenen = in the evening
• om natten = at night / during the night

In this kind of time expression, Danish usually uses the definite form:

• morgenen
• aftenen
• natten

So om aftenen is the normal idiomatic phrase.

Even though English says in the evening with the, Danish builds it into the noun ending:

• aften = evening
• aftenen = the evening

So om aftenen is the natural fixed expression.

In Danish, hvis is the usual word for if in conditional sentences.

So:

• hvis du vil gå i seng tidligt = if you want to go to bed early

Danish om can sometimes mean whether/if, but usually not in the same way as English conditional if.

For example:

• Jeg ved ikke, om han kommer. = I don’t know whether he is coming.

But in your sentence, the meaning is conditional, so hvis is the correct choice.

Here vil means want to, not simple future.

So:

• du vil gå i seng tidligt = you want to go to bed early

That is a very important point, because English will often marks the future, but Danish vil frequently means want to or be willing to.

If you translated it too literally as future will, you might misunderstand the sentence.

Here the idea is:

• if you want to go to bed early

not

• if you will go to bed early

Gå i seng literally means go in(to) bed, but in normal English we say go to bed.

It is a fixed expression in Danish:

• gå i seng = go to bed
• være i seng = be in bed

There is no article because Danish often uses fixed idiomatic expressions without one, just as English does in some cases.

Compare:

• Han er i skole. = He is at school.
• Hun går i seng tidligt. = She goes to bed early.

So you should learn gå i seng as a set phrase.

Because tidligt is being used as an adverb here.

• tidlig = early (adjective form)
• tidligt = early (adverb form)

In this sentence, tidligt describes the verb phrase gå i seng:

• gå i seng tidligt = go to bed early

That is why Danish uses the -t form.

Compare:

• en tidlig morgen = an early morning
• han kom tidligt = he arrived early

Yes, absolutely.

You can also say:

• Hvis du vil gå i seng tidligt, så lad være med at drikke kaffe om aftenen.

This means the same thing.

When the hvis clause comes first, the main clause still follows normal Danish main-clause word order. You will often see så after the conditional clause, but it is not always required.

So both are natural:

• Lad være med at drikke kaffe om aftenen, hvis du vil gå i seng tidligt.
• Hvis du vil gå i seng tidligt, så lad være med at drikke kaffe om aftenen.

Usually it means evenings in general.

Because of om aftenen, the sentence sounds like general advice:

• Don’t drink coffee in the evening if you want to go to bed early.

If you wanted to talk about this evening, Danish would usually use something like:

• i aften = tonight / this evening

So there is a clear difference:

• om aftenen = in the evening, generally
• i aften = tonight, this specific evening

There is no past tense here.

The sentence contains:

• an imperative: Lad være
• infinitives: at drikke, gå
• a present-tense verb: vil

But overall, the sentence is giving advice or a command, not describing a past or completed action.

So the structure is basically:

• negative command
  • conditional clause

That is why it feels timeless and general rather than tied to a specific moment in the past or future.

A natural stress pattern would usually emphasize the key meaning words:

Lad være med at drikke kaffe om aftenen, hvis du vil gå i seng tidligt.

The strongest stress often falls on words like:

• drikke
• kaffe
• aftenen
• gå i seng
• tidligt

Small grammar words like med, at, du, and sometimes hvis are usually less stressed.

So in natural speech, the sentence flows more by meaning than word-by-word pronunciation.