( ( ( ( ( ( The universe ) ( contains ( billions ( of galaxies ) ) ) ) , ) and ) ( ( each galaxy ) ( contains ( billions ( of ( ( stars , ) ( which ( ( are frequently ) ( ( bunched together ) ( in ( ( star clusters ) ( of ( as ( many ( as 100,000 ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) . )
(ROOT (S (S (NP (DT The) (NN universe)) (VP (VBZ contains) (NP (NP (NNS billions)) (PP (IN of) (NP (NNS galaxies)))))) (, ,) (CC and) (S (NP (DT each) (NN galaxy)) (VP (VBZ contains) (NP (NP (NNS billions)) (PP (IN of) (NP (NP (NNS stars)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBP are) (ADVP (RB frequently)) (VP (VBN bunched) (ADVP (RB together)) (PP (IN in) (NP (NP (NN star) (NNS clusters)) (PP (IN of) (NP (QP (RB as) (JJ many) (IN as) (CD 100,000))))))))))))))) (. .)))
The universe contains billions of galaxies, and each galaxy contains billions of stars, which are frequently bunched together in star clusters of as many as 100,000.
(ROOT (S (NP (DT A) (NN galaxy)) (VP (VBZ is) (VP (RBS best) (VBN described) (PP (IN as) (NP (NP (DT a) (NN cluster)) (PP (IN of) (NP (NP (NNS billions)) (PP (IN of) (NP (NNS stars))))))))) (. .)))