It can be confusing. Maybe I can help. First of all Spanish and English have similar parts of speech, but sometimes there is a definite difference. In English we have a present participle and is used for the progressive tenses for example, "I am speaking" can be translated as estoy hablando. This use is the same in English as in Spanish.
However, what is know as the present participle in English is called the gerundio in Spanish. The difference is that in English we can use the present participle as a noun,-ing and it is known as the gerund but it can not be done in Spanish. That is the difference part.
Notice the English gerund is not the same as the Spanish gerundio (the present participle is the same as the Spanish gerundio. So how does Spanish get around this? It uses the infinitive. So when in English the present participle (--ing) is used as a noun, Spanish uses the infinitive, just like in the Duo sentence 'por participar' is translated as 'for participating'.
Any word following a preposition is a noun, and in the Duo sentence 'por' is the preposition. Therefore the infinitive has to be used because the Spanish Gerundio, can not be a noun. CLICK HERE FOR MORE INFO
Thank you! Yes, that is very helpful! I really enjoy DL, but, I can't always pick up grammar strictly from a bunch of examples. Occasionally, I need to have it spelled out. :)
In this case, I admit to having made an assumption, that gerunds and gerundio were the same. I know, never assume. :) However, my big problem is that, in the DL world, the rules tend to fluctuate from example to example. The purpose of all the examples is to let us find the pattern for ourselves - which is a great way to learn! - but, if the examples don't line up, then it is easy to create a pattern that isn't the whole picture. Sort of like the "Special Theory of Relativity," an answer for the stuff that didn't fit the first time. ;)
Thanks again for taking the time. Definitely helped!
Participando translates to "participating", too, but it's a different -ing form. This is the present participle, which is used as either an adjective (un home participando - a participating man) or in progressive tenses (El hombre está participando - The man in participating.)
This sentence, on the other hand, uses the Gerund, which is used as a noun-like form. Whenever you can replace an -ing form with a different noun and it still makes sense, you're using a Gerund: "Thank you for your time", for instance. Spanish uses the infinitive form for that purpose.
"Can you say Gracias por participando"
The simple answer is no. A gerundio / past participle can NEVER be proceeded by a preposition in Spanish. The Spanish gerundio never acts as a noun. You must use the infinitive for this purpose. The translation of that infinitive into English will often be be use of the gerund (-ing) form, but this does not make it OK to use the gerundio in Spanish.