When you're talking about nonspecific things.
it's like (a) and (an) in english.
uno is for singular masculine.
una is for singular feminine.
unos is for plural masculine.
unas is for plural feminine.
Answer:
Cantar = To Sing
Explanation:
You can use this in a sentence for example:
I was able to sing when I was 5, but now I like drama more.
Cuando tenía cinco años podía cantar, pero ahora me gusta el arte de teatro mas
