Bussen kör förbi polisstationen.

Because bussen means the bus, while en buss means a bus.

Swedish usually puts the definite article at the end of the noun:

• en buss = a bus
• bussen = the bus

So Bussen kör förbi polisstationen starts with the bus, not a bus.

For the same reason: Swedish often adds the as a suffix.

• en polisstation = a police station
• polisstationen = the police station

So Swedish does not normally say a separate word like English the here. The definiteness is built into the noun itself.

Kör förbi means drives past or goes past by driving.

So the sentence means that the bus passes the police station without stopping there.

A few related examples:

• Bilen kör förbi huset. = The car drives past the house.
• Hon går förbi skolan. = She walks past the school.

The word förbi adds the idea of movement past something.

In this sentence, it is best understood as part of the expression köra förbi, much like a phrasal verb in English.

So:

• köra = drive
• köra förbi = drive past

This is very common in Swedish. The same förbi can combine with other verbs too:

• gå förbi = walk past
• åka förbi = go past / ride past
• titta förbi = stop by

So here, förbi is adding an important meaning to the verb.

Because köra is the natural verb when a vehicle is being driven.

With a bus, car, or truck as the subject, Swedish often uses köra:

• Bussen kör förbi polisstationen.
• Bilen kör snabbt.

By contrast, åka is very common when a person is travelling or riding:

• Jag åker buss. = I go by bus / I ride the bus.
• Vi åker till stan. = We’re going to town.

A useful way to remember it:

• the driver/vehicle often kör
• the passenger usually åker

Kör is the present tense of köra.

• köra = to drive
• kör = drive / drives / is driving

Just like English present forms, Swedish kör can describe:

• something happening now
• something that happens regularly
• a general fact

So depending on context, Bussen kör förbi polisstationen could mean:

• The bus is driving past the police station
• The bus drives past the police station

Swedish present tense is often broader than English.

The k in kör is not a hard English k sound. Before ö, it becomes a soft sound, roughly like sh.

So kör is approximately like shur, but with a Swedish vowel sound that does not exist exactly in English.

A rough guide:

• k before ö → soft, like sh
• ö → somewhat like the vowel in British English bird, but with rounded lips

So kör is roughly sh-ö-r.

Because Swedish makes compound nouns very freely.

Polisstationen is built like this:

• polis = police
• station = station
• polisstation = police station
• polisstationen = the police station

English often writes these as separate words, but Swedish usually joins them into one word.

This is extremely common in Swedish, so getting used to long compound nouns is important.

You would say:

Bussen kör inte förbi polisstationen.

In a main clause, inte usually comes after the finite verb:

• Bussen kör inte förbi polisstationen.

So the order is:

• Bussen = subject
• kör = finite verb
• inte = not
• förbi polisstationen = the rest

Yes. Passerar means passes.

So:

• Bussen kör förbi polisstationen.
• Bussen passerar polisstationen.

Both are natural, but they feel slightly different:

• kör förbi emphasizes the movement of driving past
• passerar is a more direct verb meaning passes

In everyday Swedish, kör förbi is very common and natural for vehicles.

That would be:

En buss kör förbi en polisstation.

Compare:

• Bussen kör förbi polisstationen. = The bus drives past the police station.
• En buss kör förbi en polisstation. = A bus drives past a police station.

So the main changes are:

• bussen → en buss
• polisstationen → en polisstation