Choose a topic and a student to begin this exercise.  Tell that student to begin a sentence about school lunches by offering the first word.  He or she says, "My."  The next student in the row says, "favorite."  The third student follows with, "food."  The fourth gives an obligatory "is," and the fifth says "pizza."  Now the sixth student has a more difficult choice.  Does he or she end the sentence with a period?  Problem is, punctuation is the "stopper" -- having to add a period, comma, colon, hyphen or any punctuation forces the student out of the game!  However, continuing without proper punctuation or using incorrect sentence structure is also a stopper.  What can Student #6 say without leaving the game?  (Hint:  A preposition might be the perfect stall tactic at this point!)