Learn Swedish: Bilen har fyra dörrar. - The car has four doors.

In Swedish, "the" isn't a separate word like in English. Instead, it gets attached to the end of the noun as a suffix. The basic word for "a car" is en bil. To say "the car", you add -en to the end, making it bilen.

Is har used for both "has" and "have"?

Yes! Swedish verbs are very friendly because they don't change based on who is doing the action. Whether it is I have (jag har), they have (de har), or the car has (bilen har), the present tense verb stays exactly the same.

How is the plural word dörrar (doors) formed from the singular?

The singular word for "a door" is en dörr. To make it plural, you add the ending -ar, which gives you dörrar (doors). This is a very common way to make plural nouns in Swedish, especially for words that use en.

If I wanted to say "the doors" instead of "four doors", would it still be dörrar?

No, dörrar just means "doors" in general. If you want to say "the doors" (the definite plural), you have to add another ending. For plurals ending in -ar, you add -na, making it dörrarna. Here, we just need "four doors", so we stick to fyra dörrar.