Gick vi inte vilse? Jo, det gjorde vi.

Because this is a yes/no question in Swedish. In main-clause yes/no questions, the finite verb comes first.

• Statement: Vi gick inte vilse. = We didn’t get lost.
• Question: Gick vi inte vilse? = Didn’t we get lost?

So Swedish forms this kind of question by putting the verb before the subject, much like English Did we... ?

Vilse means lost or astray.

In this sentence, it appears in the common expression gå vilse, which means:

• to get lost
• literally something like to go astray

So gick vilse means got lost.

Yes. Gå vilse is a very common Swedish expression meaning to get lost.

Examples:

• Jag gick vilse i skogen. = I got lost in the forest.
• Vi gick vilse i stan. = We got lost in town.

Even though gå usually means to go or to walk, in this expression the whole phrase should be learned together as get lost.

Because in Swedish main clauses, inte usually comes after the finite verb and after the subject.

So in a normal statement:

• Vi gick inte vilse.

And in a yes/no question, the verb moves to first position, but inte still stays after the subject:

• Gick vi inte vilse?

So the order is:

• Verb + subject + inte + rest

Gick is the past tense (preterite) of gå.

• gå = to go
• gick = went

But in the expression gå vilse, English usually translates it as got lost, not went lost.

So:

• Vi gick vilse = We got lost

This is one of the most important things in the sentence.

In Swedish, jo is used to answer yes to a negative question or negative statement.

So if someone asks:

• Gick vi inte vilse? = Didn’t we get lost?

and the answer is actually yes, we did, Swedish uses:

• Jo

not ja.

A useful way to think of it:

• ja = yes, to a positive question
• jo = yes, in contradiction to something negative

Use ja after a positive question.

For example:

• Gick vi vilse? = Did we get lost?
• Ja, det gjorde vi. = Yes, we did.

But with a negative question:

• Gick vi inte vilse? = Didn’t we get lost?
• Jo, det gjorde vi. = Yes, we did.

So the difference is about whether the question is negative.

Here, jo means something like:

• Yes, actually we did
• On the contrary, we did

It pushes back against the negative idea in the question.

So Jo, det gjorde vi means: Yes, we did get lost, despite the negative wording of the question.

Swedish often uses göra (to do) to refer back to an action that was just mentioned, much like English does in Yes, we did.

So:

• Jo, det gjorde vi.

literally looks like:

• Yes, that did we

but naturally means:

• Yes, we did.

Here, det refers back to the whole idea of getting lost.

Because Swedish often uses göra as a kind of pro-verb, similar to English do.

Compare:

• Question: Gick vi inte vilse?
• Answer: Jo, det gjorde vi.

English does the same thing:

• Didn’t we get lost?
• Yes, we did.

You could repeat the whole verb phrase in Swedish, but det gjorde vi is very natural and common.

Gjorde is the past tense of göra, which means to do.

• göra = to do
• gjorde = did

So det gjorde vi literally contains did, just like English we did.

Yes. In conversation, Jo by itself can be enough.

For example:

• Gick vi inte vilse?
• Jo.

That means Yes, we did.

But Jo, det gjorde vi is fuller and clearer.

The difference is the negative.

• Gick vi vilse? = Did we get lost?
• Gick vi inte vilse? = Didn’t we get lost?

The negative version often suggests that the speaker expects confirmation, is surprised, or thinks the answer is probably yes.

So Gick vi inte vilse? can sound like:

• Didn’t we get lost?
• Surely we got lost, didn’t we?

The exact nuance depends on context and intonation.

The statement would be:

• Vi gick inte vilse. = We didn’t get lost.

To turn it into the question shown here, Swedish moves the finite verb to the front:

• Gick vi inte vilse?

So this is a good pair to compare:

• Vi gick inte vilse. = We didn’t get lost.
• Gick vi inte vilse? = Didn’t we get lost?

Yes. Without inte, the meaning changes completely.

• Gick vi vilse? = Did we get lost?
• Gick vi inte vilse? = Didn’t we get lost?

So inte is crucial: it makes the question negative.

That is also why the answer needs jo rather than ja.

Yes, very common.

This pattern appears all the time:

• negative question or statement
• followed by jo
• and often a short confirmation with det gjorde jag/du/vi/de

Examples:

• Du såg honom inte? = You didn’t see him?
• Jo, det gjorde jag. = Yes, I did.

So the sentence you have is a very useful model for everyday Swedish.