Learn Swedish: Eftersom kopplingen var trasig, så underkände inspektören eleven. - Since the clutch was broken, the inspector failed the student.

In Swedish, when a sentence starts with a subordinate clause like Eftersom kopplingen var trasig, you can use så as a resumptive adverb to link it to the main clause. It essentially sums up the first clause so the main clause can begin smoothly. It is optional but extremely common, especially in spoken Swedish.

How does using så affect the V2 (verb-second) word order here?

The entire subordinate clause acts as the first position in the sentence. When you add så, it takes over that first position, summarizing the condition. Because Swedish requires the verb in the second position in a main clause, the verb underkände must come immediately after så, pushing the subject inspektören to the other side of the verb.

Can I drop så and still have a correct sentence?

Yes! You can absolutely write Eftersom kopplingen var trasig underkände inspektören eleven. Dropping så makes the sentence sound slightly more formal and better suited for written text, while keeping it is very natural for everyday speech.

Could I use underkände to say that the student failed the test?