( ( Tropical precipitation ) ( ( ( is primarily ) convective ) . ) )
(ROOT (S (NP (JJ Tropical) (NN precipitation)) (VP (VBZ is) (ADVP (RB primarily)) (ADJP (JJ convective))) (. .)))
Tropical precipitation is primarily convective.
(ROOT (S (NP (NNP Groundwater)) (ADVP (RB primarily)) (VP (VBZ comes) (PP (IN from) (NP (NN precipitation)))) (. .)))