How to do an underhand serve<br>Get your feet into position. Stand with your non-dominant foot in front with your toes facing forward. Your dominant foot should be in the back with toes pointed slightly out.
Serving in both tennis and volleyball require a specific stance to be more effective. 
( z1 require :ARG0 ( z2 serve :ARG1 ( z3 and :op ( z4 tennis ) :op ( z5 volleyball ) :mod ( z6 both ) ) ) :ARG1 ( z7 stand :ARG1-of ( z8 specific ) :purpose ( z9 effective :ARG0 z2 :ARG2-of ( z10 have-degree :ARG1 z2 :ARG3 ( z11 more ) ) ) ) )