Questions & Answers about Den där killen blev så anfådd att han snubblade.
How does the så ... att construction work in this sentence?
It connects a state or degree (så anfådd) with its consequence (att han snubblade). It works exactly like "so ... that" in English. Så comes right before the adjective, and att starts a new clause to explain the result of being so out of breath.
Why is it killen (the guy) rather than just kille (guy) after den där?
In Swedish, demonstratives like den där (that) and den här (this) always require the noun to be in its definite form. You are literally saying "that the guy". If you just said den där kille, it would be grammatically incorrect.
Could I use var (was) instead of blev (became) here?
You could, but it changes the meaning slightly. Blev (the past tense of bli) emphasizes the change in his condition—he got out of breath from doing something. Var would just describe an ongoing state (he was out of breath).
What would happen to the word order if I wanted to say "so out of breath that he didn't stumble"?