Du skal tage låget af.

In this sentence, skal mainly expresses necessity, instruction, or obligation: you have to / you need to.

So Du skal tage låget af is understood as something like:

• You need to take the lid off
• You have to remove the lid

Danish skal can sometimes refer to the future, but in a sentence like this, it usually means someone is supposed to do something.

Because tage ... af works like a phrasal/separable verb idea, similar to English take ... off.

Here:

• tage = take
• af = off
• låget = the lid

So the object goes between the verb and the particle:

• tage låget af = take the lid off

This is very natural in Danish. English does something similar:

• take the lid off
• not normally take off the lid in every context, though that is also possible in English

In Danish, tage af on its own is not the point here; the full expression is tage noget af = take something off/remove something.

Because låget means the lid, while låg means lid in a more dictionary-like/basic form.

Danish often makes the definite form by adding the article to the end of the noun.

For et-word nouns:

• et låg = a lid
• låget = the lid

So in this sentence, we are talking about a specific lid, which is why Danish uses låget.

Because låg is a neuter noun in Danish, so it takes et in the indefinite form:

• et låg

Neuter nouns normally form the definite singular with -et:

• låget = the lid

If it were a common gender noun, it would usually take -en instead. So lågen would suggest a different noun pattern, and it is not the correct definite form of låg.

Because after a modal verb like skal, Danish normally uses the bare infinitive.

So:

• Du skal tage låget af
• not Du skal at tage låget af

This is similar to English:

• You must take the lid off
• not You must to take the lid off

Other Danish modal verbs work the same way, for example:

• kan = can
• vil = will/want to
• må = may/must
• skal = shall/must/need to

The basic verb is tage, which means to take.

Its forms include:

• at tage = to take
• tager = take/takes
• tog = took
• taget = taken

It may look unfamiliar at first, but it is a very common Danish verb. In everyday speech, you may also hear the shortened spoken form ta’ instead of tage.

For example:

• Tag låget af! = Take the lid off!
• Colloquially, this may sound more like Ta’ låget af!

Not exactly.

Du skal tage låget af means something like:

• You need to take the lid off
• You are supposed to take the lid off

It sounds more like an instruction, requirement, or statement of what someone should do.

A direct command would usually be:

• Tag låget af! = Take the lid off!

So the difference is roughly:

• Du skal tage låget af = instruction/obligation
• Tag låget af! = direct imperative

Yes. Af is a very common Danish word and can have several meanings depending on context, including:

• off
• of
• sometimes part of fixed expressions

But in tage låget af, it clearly means off.

So you should learn the whole expression:

• tage noget af = take/remove something off

That will be more useful than trying to translate af the same way in every sentence.

The structure is:

• Du = subject
• skal = finite verb
• tage = infinitive
• låget = object
• af = particle/preposition-like element

So:

• Du skal tage låget af

This is normal Danish word order after a modal verb:

subject + modal verb + infinitive + object + particle

The placement of af after the object is natural because it belongs with tage in the expression tage ... af.

In careful standard Danish, you may see:

• Du skal tage låget af.

In everyday speech, tage is often reduced, so it may sound more like:

• Du skal ta’ låget af.

If it is a direct instruction, people very often say:

• Tag låget af!

So the written sentence is completely normal, but in speech you should expect a shorter pronunciation of tage.

A rough guide for English speakers is:

• låg has a long vowel somewhat like the vowel in British law, but not exactly the same
• -et in låget is usually a weak ending

A very rough approximation might be something like LAW-yeth or LAW-uh, depending on accent and how carefully it is spoken, but no English spelling matches it perfectly.

The important things to notice are:

• the Danish å sound
• the soft, unstressed ending in -et
• the fact that spoken Danish often reduces endings quite a lot

If you are learning pronunciation, it is best to listen to native audio rather than rely on English-style spelling.