Vi vandrade längs kusten.

Vi means we.

In Swedish, subject pronouns are usually stated explicitly, just like in English, so vi is needed here.

Vandrade is the past tense of the verb vandra.

• vandra = to hike, wander, trek, walk
• vandrade = walked / hiked / wandered

In this sentence, it tells you the action happened in the past.

No. In Swedish, verbs do not change depending on the subject.

So you get:

• jag vandrade = I walked
• du vandrade = you walked
• vi vandrade = we walked
• de vandrade = they walked

This is much simpler than English, where only a few forms change, and much simpler than many other European languages.

All of them can relate to walking, but they are not exactly the same.

• gå = go, walk; the most general word
• promenera = take a walk, stroll
• vandra = hike, trek, wander, walk over some distance, often in nature

So vandrade gives a sense of walking along a route or landscape, not just ordinary everyday walking.

Längs is a preposition meaning along.

It is used when something happens or moves following the side or length of something:

• längs vägen = along the road
• längs floden = along the river
• längs kusten = along the coast

So in this sentence, it shows the path of the walking.

Because Swedish often uses the definite form where English may say the.

• en kust = a coast
• kusten = the coast

Swedish usually puts definiteness at the end of the noun with a suffix, instead of using a separate word like the.

So:

• längs kust would sound wrong here
• längs kusten = along the coast

It is singular definite.

• kust = coast
• kusten = the coast
• kuster = coasts
• kusterna = the coasts

So the sentence refers to one coast, or one coastal stretch understood in context.

Yes, but Swedish follows V2 word order in main clauses, which means the finite verb usually stays in the second position.

The neutral order here is:

• Vi vandrade längs kusten.

You could also say:

• Längs kusten vandrade vi.

That version is more marked or literary, but still grammatical. Notice that when längs kusten comes first, the verb vandrade still stays in second position, and vi moves after the verb.

A rough guide for an English speaker:

• längs: the ä is somewhat like the vowel in British bed, but not exactly; the final ngs is pronounced as one cluster
• kusten: roughly KOOS-ten, but with a short Swedish u that does not match English perfectly

A very rough full pronunciation might sound like:

• Vi VAND-rade lengs KOO-sten

But that is only approximate. The biggest things to watch are:

• Swedish ä in längs
• Swedish u in kusten
• the stress: VANdrade, KUSten

Yes. Depending on context, vandrade can be translated in several natural ways, such as:

• we walked along the coast
• we hiked along the coast
• we wandered along the coast

The exact English choice depends on the situation, but the Swedish sentence itself is completely natural.

Yes. It shows a common past-tense pattern for many Swedish verbs.

For verbs like vandra, the pattern is:

• infinitive: vandra
• present: vandrar
• past: vandrade
• supine: vandrat

This is a regular pattern, so once you learn it, many verbs work similarly.