Mrs. Jones' cat isn't feeling well due to a bad case of constipation. She takes it to the vet, who prescribes a new laxative. "Give her about six teaspoons of this," the vet says, "and she'll be better in no time."
Mrs. Jones follows the instructions and returns a week later. The vet asks, "How's your calf?"
"I don't have a calf," Mrs. Jones replies. "It was my cat who wasn't feeling well."
"Well, how's your cat doing?" the vet inquires.
"I'm not sure," says Mrs. Jones. "The last time I saw her, she was heading toward the north end of town with ten other cats. Five were digging, three were covering, and two were scouting for new territory."