In English, we say "I swim" and "I practice swimming" or "I am swimming". I want to know how to say "I practice swimming" in Spanish. http://www.dummies.com/how-to/content/conjugating-the-spanish-verb-nadar-to-swim.html this site has all the ways to say "nadar" (nada, nadar, nadamos, nadan, ect...) but they don't say the translation of "swimming", the only show "I swim". I think the right way to say this is "Yo practico nadar". Is this correct? What is the correct conjugation of verb in general when you add an "-ing" to the English equivalent? Is there some rule I can remember?
In English you can use the -ing form of the verbs to build a noun representing the action performed by that verb. This is only one of the many uses of -ing forms.
In this case, "swimming" must be translated in Spanish as what it represents in your utterance, that is to say, natación:
Yo practico natación.
Be very careful with literal translations, transforming the -ing form in English to the Spanish gerund, because in such a case you could end up with something like:
Yo practico nadando.
That is not what you mean in this case.
You can also use the very polysemic verb
hacer (to do):
Another possibility with
practicar is to add the corresponding definite article to
Practico la natación.
I'm not very sure of this, but I think that this form (with the article) is more typical of Spain as compared to Latin American varieties of Spanish.
NOTE : These are not practical translations
I suppose you could say something like these examples, if you're just dead set on using the infinitive.
El nadar lo practico
Practico el nadar.
Practico a nadar
Practicar is a transitive verb meaning it requires an object. If it is ever used intransitively, then it is because the object was defined prior, the object is already in context.
For example, if you walked into a room full of people and said, "¡A practiar!", you would of course be saying "Let's practice!", but what if you were a stranger to this room? By randomly walking into the room full of people you have no connection or relationship with and saying "let's practice", you will have confused everyone because they are hanging on for that object. "WTF are we practicing?"
Nadando is not an object. Like everyone else has said, it is a gerund conjugation of nadar.
If you want to refer to something in the way your questioning about, the way we do in English with the gerunds, then you just take the infinitive form of the verb and slap a definite article in front of it; make it an object
Me gusta el nadar / I like swimming.
A veces practico el boxear / Sometimes I practice boxing.
Even though both of those objects have their own noun forms,
boxeo respectively, they are still grammatically correct, as far as I know.