1. Being dry almost the whole year.
Grasslands receive very little rainfall a year, which means they are usually dry.
2. Continental
The summers are not too hot, neither are the winters very cold.
3. Cooler
They are generally cooler at higher elevations, especially on mountains and high hills.
4. I believe thin rings.
I'm not completely sure about this one, I think you'll have to do more research, but this is my guess.
I hope this helped!