"The pretty woman is swimming."
Translation:예쁜 여자가 수영하고 있어요.
I know it is an never ending question, but I am confused in this specific case. What would be the difference between 예쁜 여자는 수영하고 있어요 and 예쁜 여자가 수영하고 있어요?
As far as I understood, both particles are grammaticaly right, but then it is a "context thing" (depending on what we are focusing on, the topic and subjet and so on). But here - as most of the times with Duolingo - there is no context, so I believe both should be accepted? Or have I got it totally wrong?