Picking The Right Worm

"Hey, Duck, what are you doing here? Every time I see you dip your head into the water and gulp. What's going on?" asked the hipp.

"I am having my breakfast on worms. You know, it's hard to find these worms, and picking the right worm to eat is an art. Not everybody can do it, but I am an expert," the duck proudly declared. The hippo laughed.