( Viruses ( ( cause ( ( colds and ) flu ) ) . ) )
(ROOT (S (NP (NNS Viruses)) (VP (VBP cause) (NP (NNS colds) (CC and) (NN flu))) (. .)))
Viruses cause colds and flu.
(ROOT (S (NP (NP (DT The) (JJ common) (NN cold)) (CC and) (NP (NN flu))) (VP (VBP are) (NP (NP (NNS examples)) (PP (IN of) (NP (NP (JJ human) (NNS diseases)) (VP (VBN caused) (PP (IN by) (NP (NNS viruses)))))))) (. .)))