Two black and white dogs are being walked along the beach by their owners, who stop to talk.
Twee zwarte en witte honden worden langs het strand gelopen door hun eigenaren, die stoppen om te praten.
Two black and white dogs are not being walked
Twee zwarte en witte honden worden niet gewandeld.
Dogs are either being walked or not being walked not both.
Honden worden wel of niet gewandeld.