Jag vet inte vad mejlet gäller.

Here, gäller means something like concerns or is about.

• gälla = to concern, apply to, be about
• gäller = present tense

So the sentence uses gälla in the sense of what the email concerns / what the email is about.

In everyday Swedish, many people would also say handlar om:

• Jag vet inte vad mejlet handlar om.

That version is often a bit more conversational.

Gäller is the present tense of the verb gälla.

Some useful forms are:

• infinitive: gälla
• present: gäller
• past: gällde
• supine: gällt

So in this sentence, the speaker is saying what they do not know now.

Because mejlet is the definite singular form: the email.

Swedish usually adds the definite article to the end of the noun:

• ett mejl = an email
• mejlet = the email

So mejlet tells you we are talking about a specific email, not just any email.

In a normal Swedish main clause, inte usually comes after the finite verb.

So:

• Jag vet inte = I do not know

This is standard Swedish word order.

Compare:

• Jag kommer inte. = I am not coming.
• Hon förstår inte. = She does not understand.

So vet inte is exactly what you should expect.

Because this is an embedded question after Jag vet inte.

In Swedish, embedded questions normally use subject + verb order:

• vad mejlet gäller

Here:

• vad = what
• mejlet = the subject of the embedded clause
• gäller = the verb

A direct question would more likely have verb-second order:

• Vad gäller mejlet?

But after Jag vet inte, Swedish switches to embedded-clause word order:

• Jag vet inte vad mejlet gäller.

This is a very important pattern in Swedish.

Yes. Vad stands for the thing that the email concerns.

You can think of it like this:

• Mejlet gäller mötet. = The email concerns the meeting.
• Jag vet inte vad mejlet gäller. = I do not know what the email concerns.

So vad is functioning as the thing being asked about.

Because Swedish does not need one with gälla.

In English, you often say:

• what the email is about

But Swedish uses the verb gälla, which already contains that idea:

• vad mejlet gäller

So there is no extra om here.

If you use handla om, then you do need om:

• vad mejlet handlar om

Both are understandable, but the grammar is different.

Because Swedish does not need a dummy pronoun there.

English often says:

• I don't know what the email is about
• or I don't know what it is about

Swedish does not need an extra det in this structure:

• Jag vet inte vad mejlet gäller.

The subject is already mejlet, so the sentence is structurally complete.

Yes, absolutely.

That is a very common and natural alternative, and many learners will hear it more often in conversation.

Compare:

• Jag vet inte vad mejlet gäller. = I do not know what the email concerns / is about.
• Jag vet inte vad mejlet handlar om. = I do not know what the email is about.

A rough nuance:

• gälla can sound a little more formal or abstract
• handla om often sounds more everyday and conversational

Both are correct in the right context.

Sometimes, yes — and that can confuse learners.

There is a fixed expression:

• vad gäller ... = as for ... / regarding ...

For example:

• Vad gäller tiderna, får vi återkomma. = As for the times, we will get back to you.

But in Jag vet inte vad mejlet gäller, that is not the fixed expression. Here, vad belongs to the embedded question, and mejlet is the subject:

• vad mejlet gäller = what the email concerns

So even though the same words appear, the grammar is different.

Yes, mejl and mejlet are normal Swedish words.

Common options are:

• mejl = email
• mejlet = the email
• e-post = email
• e-postmeddelande = email message

Mejl is a very common modern spelling in Swedish. You may also see mail informally, but mejl is the standard Swedish-style spelling.

Usually, no.

Swedish generally uses fewer commas than English before subordinate clauses. So this sentence is normally written as:

• Jag vet inte vad mejlet gäller.

No comma is needed.

A rough guide:

• mejlet ≈ MAY-let
• gäller ≈ YEL-er or YEL-ler

A couple of notes:

• In gäller, the g is soft before ä, so it sounds like y.
• The stress is on the first syllable in both words.

So:

• MEJ-let
• GÄL-ler