"Ze heeft vijftien jurken."
Translation:She has fifteen dresses.
You need to check the settings (your mic has to be on, and then you need to check the settings on the app, of course -you can have different setting for different language courses I believe).
I think it also has to do with what your native language is and how much exposure you get. In my case, I watch the news in Dutch every weekend (last year I used to watch them every day, but this year I'm a lot busier so it's become impossible :P ).