( ( Gauge bosons ) ( ( are ( ( ( carrier particles ) ( for three ) ) ( of ( the ( four ( fundamental forces ) ) ) ) ) ) . ) )
(ROOT (S (NP (JJ Gauge) (NNS bosons)) (VP (VBP are) (NP (NP (NN carrier) (NNS particles)) (PP (IN for) (NP (CD three))) (PP (IN of) (NP (DT the) (CD four) (JJ fundamental) (NNS forces))))) (. .)))
Gauge bosons are carrier particles for three of the four fundamental forces.
(ROOT (S (NP (EX There)) (VP (VBP are) (NP (NP (CD four) (NNS types)) (PP (IN of) (NP (NNS bosons))))) (. .)))