Verbs converted to nouns: when are articles needed

Question

The lesson gave me the impression that articles are only needed when they are in plural form, but based on the discussion below it sounds like they are always needed for both singular and plural forms. Is that correct?  So that’s why “el cantar” was correct in the quiz question but “cantar” alone was incorrect?  How do we know when a verb is considered a noun without a quiz hint?

Silvia Píriz · Accepted Answer

Hola Pat B.
When an infinitive is used as a noun, it normally takes the definite article:
El cantar de los pájaros me relaja.
El comer bien es importante.
So yes, in the quiz el cantar was required because cantar was functioning as a noun ("singing" or "the act of singing"), not as a verb.
By contrast, when the infinitive is functioning as a verb, no article is used:
Me gusta cantar.
Quiero comer.
Es importante estudiar.
The key is to identify the role of the infinitive in the sentence. If it names an activity or concept (i.e. it behaves like a noun), it generally takes the definite article. If it expresses an action (i.e. it behaves like a verb), it does not.
I hope this helps clarify the distinction!
Silvia