Leo: Given the sentence "A dirt biker competes while onlookers watch." is it true that "A dirt biker competes while onlookers watch and wave their signs and flags."?
Mei: OK, So, let's think first...
Me:
A dirt biker competes while onlookers watch does not imply that the onlookers wave their signs and flags.
Thus, the answer is it is not possible to tell.