Sound like the start of an Iron Man competition.
How many people have written it once, copied and then pasted? ;)
Why is the fourth "you" missing? Either four or just one "you" would be correct.
I guess that slipped in somewhere. Feel free to report it if it pains you. :)
Why can four "you", one is not enough?
You can include the "you" all four times if you really want to emphasize the repetition. Or you can just include the first one. Either way is fine.
Why not just: Swim there, run back, swim there, run back.?
How would this be translated into Hungarian?
That would not indicate who is running and swimming. " You" needs to be included, otherwise it is an instruction for which the imperative form of the verb would be required and we haven't come to that yet.
That is an imperative, which is not used here
Imperative, yes. It's an order:
Odaússz, visszafuss, odaússz, visszafuss.
If either using all four 'you's is fine my answer should be marked correct.
Geez the English translations in this lesson are worse than usual