Om butiken är stängd, handlar jag på marknaden i stället.

Om means if here. It introduces a condition:

• Om butiken är stängd = If the shop is closed

This is a very common way to begin a conditional sentence in Swedish.

Butiken is the definite form of butik, so it means the shop.

In Swedish, the definite article is usually attached to the end of the noun:

• en butik = a shop
• butiken = the shop

Because the sentence refers to a specific shop, Swedish uses butiken.

Yes. In this sentence, stängd works like an adjective and means closed.

So:

• butiken är stängd = the shop is closed

It agrees with the noun:

• en butik → stängd
• ett fönster → stängt
• butikerna → stängda

So stängd is used because butik is a common-gender (en) noun in the singular.

Because Swedish normally puts the finite verb early in the clause.

In this subordinate clause:

• Om butiken är stängd

the order is:

• om
  • subject + verb + complement

So:

• butiken = subject
• är = verb
• stängd = complement

That is the normal order in a Swedish subordinate clause.

This is because Swedish follows the V2 rule in main clauses: the finite verb usually comes in the second position.

The first position here is taken by the whole subordinate clause:

• Om butiken är stängd

So in the main clause, the verb must come next:

• handlar jag på marknaden i stället

Compare:

• Jag handlar på marknaden i stället.
• Om butiken är stängd, handlar jag på marknaden i stället.

When something else comes first, the subject usually moves after the verb.

Handlar is the present tense of handla.

Here it means shop or do my shopping.

So:

• jag handlar = I shop / I do my shopping

With på, it often means shopping at a place:

• handla på marknaden = shop at the market

In other contexts, handla can also mean buy depending on the sentence.

Swedish often uses på for places where you shop, study, work, or participate in activities, even when English might use at or in.

So:

• på marknaden = at the market
• på affären can mean at the shop
• på jobbet = at work

Using i would sound wrong here. I usually means physically in/inside something.

I stället means instead.

So:

• handlar jag på marknaden i stället = I shop at the market instead

It is written as two words in Swedish.

You may also see the fuller expression i stället för, which means instead of:

• i stället för butiken = instead of the shop

Not always. In modern Swedish, the comma after an introductory subordinate clause is often optional.

So both of these are possible:

• Om butiken är stängd handlar jag på marknaden i stället.
• Om butiken är stängd, handlar jag på marknaden i stället.

The comma can make the sentence easier to read, especially for learners, but it is not always required.

Yes, often you could.

Both butik and affär can mean shop/store, but there can be a slight difference in feel:

• butik often sounds like a physical shop/store
• affär can also mean shop, but in some contexts it can mean business or deal

In everyday Swedish, both may be understood, but butik is very straightforward and common for shop/store.

The sentence is built like this:

• Om
  • subordinate clause
• then main clause

More specifically:

• Om butiken är stängd = condition
• handlar jag på marknaden i stället = result

So the pattern is:

• If X, then Y

This is a very common Swedish structure for conditional sentences.