Fill "$$+$$" or~"$$-$$" in the blanks to make the equation true.~\uline{~~~~~~~~~~}~  $$6$$~~~~ $$6$$~~~~ $$6$$~~~~ $$6$$~~~~ $$6=6$$ 
Overseas Competition->Knowledge Point->Calculation Modules->Basic Concepts of Equation->Inequalities
$$6+6+6-6-6=6$$． 