Translation:Do you know how to swim?
In my first comment i was talking about normal English. If someone wanted to hire a canoe, he might be asked "Can you swim?" This would not be a question about his arthritis or intoxication, but whether at some stage in life he had learned to swim. I suspect that in Spain he would be asked "¿Sabes nadar? and if he asked "please say in English" it would be "Can you swim?"
And he might be asked "Do you know how to swim?" All I am sure of is that my two good, thick Spanish/English dictionaries have many entries for "saber," but neither uses the word "can" in any way, shape,or form in defining "saber." When I look up "can" it says "poder, be able to" and "saber, know how to." I am not trying to argue, just saying what I see.
Yes, you're right. I wasn't specific enough, my point was that different languages may use different constructions in the same situation or similar construction in different situations. "Can you swim?" is similar (of course not 100% but similar nonetheless) in meaning to "Do you know how to swim?" and you use "how" in one and not in the other. In Spanish the structure "verb + infinitive" is used with "saber" and "poder", comparing to English "can" only. Cheers :)
¿Sabes nadar? is definitely a question, so why is "you know how to swim ?" not accepted? Why is the "Do you" needed ? I am always stuck when i have a "Do You.." question and i am trying to train myself to forget the English DO YOU and go straight to the Spanish verb conjugation., Come on Duolingo, in learning Spanish from English we need to think Spanish, since we do not need to be taught an English expression,