I wonder if it works?
"shrink"
Instantly Dr Desoto is few inches smaller. He looks over and says "Hey, i shrunk"
"I guess your SHRINKing again" instantly another three inches came off of Dr desoto.
"Hey stop it, i shrubk again!"
"I know, everytime you hear the word shrink (he shrinks) you'll shrink (again!) three inches."
"Oh no! Please don't do this to me, i don't want to shrink" AARRGGHh!! i said myself and everything got bigger again.
"It's ok. As long as you don't hear the word-"
"No don't say it!"
"Shrink!"
Arrgh! De Soto was about 4 foot 10 now still standing before Matt.
Do you