A man kicking a ball should be correct as well
A pattern seems to emerge...
The 것은 term at the end of a gerund phrase can be substituted with any noun!
In this case, 것은 is substituted by the word 남자. Now the verb in the phrase is describing the man.
I'm can't figure out how duolingo is distinguishing between when "the" and "a" should be used. What's the trick here?
There's no consistent logic here... so just point it out as a mistake every time :)
A man who kicks balls?
A ball-kicking man :/?