Learn Swedish: Du måste ju tända elden innan vi fryser. - You must light the fire before we get cold, of course.

The word ju is a modal particle used when the speaker assumes the listener already knows or agrees with what is being said. Here, it adds a tone of "obviously" or "as you know." It makes the statement feel more like a shared, obvious fact rather than an abrupt order, which is why it is translated as "of course" in English.

Why is ju placed right after måste?

In a main clause, Swedish follows the V2 rule, meaning the conjugated verb comes second. Here, måste is the second element after the subject du. Modal particles like ju act as sentence adverbs, and in a standard main clause, they belong right after the first conjugated verb.

Why is the verb tända in its infinitive form instead of the present tense?

The verb tända (to light) is in the infinitive because it directly follows the modal verb måste (must). Just like in English where we say "must light" instead of "must lights", Swedish modal verbs are followed by the infinitive form of the main verb, without using the word att (to).

The English translation says "we get cold", but doesn't fryser mean "freeze"?