( and ( ( energy-efficient ( light bulbs ) ) . ) )
(ROOT (S (CC and) (VP (VB energy-efficient) (NP (JJ light) (NNS bulbs))) (. .)))
and energy-efficient light bulbs.
(ROOT (S (NP (DT A) (JJ light) (NN bulb)) (VP (VBZ converts) (NP (JJ electrical) (NN energy)) (PP (TO to) (NP (JJ light) (CC and) (JJ thermal) (NN energy)))) (. .)))