a sea of constant smiles and frequent laughter 
(ROOT (NP (NP (DT a) (NN sea)) (PP (IN of) (NP (NP (JJ constant) (NNS smiles)) (CC and) (NP (JJ frequent) (NN laughter))))))
(ROOT (NP (NP (DT ) (NN )) (PP (IN ) (NP (NP (JJ ) (NNS )) (CC ) (NP (JJ ) (NN ))))))