Vi må aflyse mødet, hvis læreren bliver syg.

In this sentence, må means must / have to, not may.

So Vi må aflyse mødet means We must cancel the meeting or We have to cancel the meeting.

This can be confusing for English speakers because Danish må can sometimes look like English may, but in many everyday sentences it expresses necessity.

A few examples:

• Jeg må gå nu. = I must leave now.
• Vi må vente. = We have to wait.

Whether it sounds more like must or have to depends on context.

Because after a modal verb like må, Danish normally uses the infinitive form of the main verb.

So:

• må = modal verb
• aflyse = infinitive, to cancel

That is why you get:

• Vi må aflyse mødet

This works like English:

• We must cancel the meeting

Other similar examples:

• Jeg kan komme. = I can come.
• Du skal arbejde. = You must/work have to work.
• Hun vil lære dansk. = She wants to / will learn Danish.

Aflyse means to cancel.

In this sentence:

• aflyse mødet = cancel the meeting

It is a very common verb for events, appointments, meetings, classes, trips, and so on.

Examples:

• De aflyser koncerten. = They are cancelling the concert.
• Toget er aflyst. = The train is cancelled.

Notice also the related past participle:

• aflyst = cancelled

Because mødet is the definite form: the meeting.

In Danish, the definite article is often added to the end of the noun rather than written as a separate word.

So:

• et møde = a meeting
• mødet = the meeting

This is very common in Danish:

• en lærer = a teacher
• læreren = the teacher
• et hus = a house
• huset = the house

So aflyse mødet literally means cancel the meeting.

For the same reason as mødet: Danish usually marks definiteness by adding an ending to the noun.

So:

• en lærer = a teacher
• læreren = the teacher

English uses a separate article (the teacher), but Danish often attaches it directly to the noun.

That means:

• hvis læreren bliver syg = if the teacher becomes ill

Hvis means if.

It introduces a condition:

• hvis læreren bliver syg = if the teacher gets sick / becomes ill

This tells you under what condition the meeting must be cancelled.

A few more examples:

• Hvis det regner, bliver vi hjemme. = If it rains, we stay home.
• Hvis du har tid, kan du komme. = If you have time, you can come.

Because in this subordinate clause, Danish keeps the normal subject-verb order:

• læreren = subject
• bliver = verb
• syg = complement

So:

• hvis læreren bliver syg

This is similar to English if the teacher becomes ill.

The main thing to remember is that the special verb-second rule belongs to main clauses. After hvis, you are in a subordinate clause, so the word order is more straightforward.

Compare:

• Main clause: Vi må aflyse mødet
• Subordinate clause: hvis læreren bliver syg

Bliver syg means becomes ill / gets sick, while er syg means is ill / is sick.

So there is a small difference:

• hvis læreren bliver syg = if the teacher gets sick
• hvis læreren er syg = if the teacher is sick

In many real situations, both could work, but bliver syg often emphasizes a change of state: the teacher was not sick before, but then becomes sick.

This is a very common pattern in Danish:

• blive træt = get tired
• blive sur = get angry
• blive gammel = grow old

Yes, in standard Danish writing, a comma before a subordinate clause like this is normal:

• Vi må aflyse mødet, hvis læreren bliver syg.

Danish comma rules can vary a bit depending on the system being taught, but in modern standard written Danish, this comma is expected here.

So for a learner, it is safest to write it with the comma.

Yes. You can also say:

• Hvis læreren bliver syg, må vi aflyse mødet.

This means the same thing.

But notice what happens in the main clause after the if-clause: Danish main clauses follow the verb-second rule. Since the Hvis læreren bliver syg clause comes first, the verb comes before the subject in the main clause:

• må vi
• not vi må

So:

• Hvis læreren bliver syg, må vi aflyse mødet.

This is a very important Danish word-order pattern.

Not exactly. Syg is the basic singular/common form meaning ill/sick.

In this sentence:

• læreren bliver syg = the teacher becomes ill

You may also see syge in other contexts, for example:

• plural
• certain adjective patterns
• definite noun phrases

Examples:

• syge børn = sick children
• den syge lærer = the sick teacher

But here, with læreren bliver syg, the correct form is syg.

A rough English-friendly pronunciation might be:

• Vi må aflyse mødet, hvis læreren bliver syg
• vee mo aw-floo-seh MØ-thid, vis LAIR-er-en BLEE-ver soo

A few useful notes:

• å in må is a rounded vowel, somewhat like the vowel in British more, but not exactly.
• y in syg is difficult for English speakers; it is a front rounded vowel not found in normal English.
• d in mødet is often soft, not a strong English d.
• bliver is often pronounced more like blee-ver in careful speech.

This rough guide is only approximate, but it can help you get started.