( WHITE ( PRISMS ; ) )
(ROOT (NP (NNP WHITE) (NNPS PRISMS) (: ;)))
WHITE PRISMS ;
(ROOT (S (NP (DT A) (NN prism)) (VP (VBZ helps) (SBAR (S (NP (NNS people)) (VP (VBP understand) (SBAR (WHNP (WP what)) (S (VP (VBZ makes) (PRT (RP up)) (NP (JJ white) (NN light))))))))) (. .)))
A prism helps people understand what makes up white light.