A teacher is explaining biology to her 4th grade students. "Human beings are the only animals that stutter", she says.   
A little girl raises her hand. "I had a kitty-cat who stuttered", she volunteered.   
The teacher, knowing how precious some of these stories could become, asked the girl to describe the incident.      
"Well", she began, "I was in the back yard with my kitty and the rottweiler who lives next door got a running start and before we knew it, he jumped over the fence into our yard!
"That must've been scary", said the teacher.
"It sure was", said the little girl. "My kitty went 'Fffff, Fffff, Fffff'... and before he could say "Fuck," the rottweiler ate him!"