"Si no corro, no camino."
Translation:If I do not run, I do not walk.
I suppose it is hard to think of all the possible correct translations. The DuoLingo staff seem to have the sentence with contractions listed as correct, but (as would be easy enough) they do not seem to have listed a version of the sentence with only one contraction. After all, it is not consistent to translate "no corro" as "I do not run" and "no camino" as "I don't walk." Though, of course, that is still correct. My rule is: When in doubt, throw the doubt-able out.