"Do dogs only see black-and-white?"
Translation:Sehen Hunde nur schwarz-weiß?
You aren't supposed to know it before you encounter it here. In English, "black and white" refers to monochromatic vision or media, not literally black and white, so it would have to be taught that German uses schwarz-weiß as the equivalent.
It also might be worth knowing that dogs see in color, although not with the same variety of colors that humans see. That won't help you with your German, but it would have been better to use the term in a better context.