( ( The sun ) ( ( is ( at ( ( the peak ) ( of ( ( an ( 11-year cycle ) ) ( of ( solar ( flare ( and ( sunspot activity ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN sun)) (VP (VBZ is) (PP (IN at) (NP (NP (DT the) (NN peak)) (PP (IN of) (NP (NP (DT an) (JJ 11-year) (NN cycle)) (PP (IN of) (NP (JJ solar) (NN flare) (CC and) (NN sunspot) (NN activity)))))))) (. .)))
The sun is at the peak of an 11-year cycle of solar flare and sunspot activity.
(ROOT (S (NP (NNS Sunspots)) (VP (VBP occur) (PP (IN in) (NP (DT a) (CD 11) (NN year) (NN cycle)))) (. .)))