( Racks ( ( ( ( ( ( keep ( ( ( bottles horizontal ) , ) ( ( their corks ) wet ) ) ) , ) and ) allow ) ( any ( sediments ( to settle ) ) ) ) . ) )
(ROOT (S (NP (NNS Racks)) (VP (VBP keep) (S (S (NP (NNS bottles)) (ADJP (JJ horizontal))) (, ,) (S (NP (PRP$ their) (NNS corks)) (ADJP (JJ wet)))) (, ,) (CC and) (VBP allow) (NP (DT any) (NNS sediments) (S (VP (TO to) (VP (VB settle)))))) (. .)))
Racks keep bottles horizontal, their corks wet, and allow any sediments to settle.
(ROOT (S (SBAR (WHADVP (WRB When)) (S (NP (NNS sediments)) (VP (VB settle) (PRT (RP out)) (PP (IN of) (NP (NN water)))))) (, ,) (NP (PRP they)) (VP (VBP form) (NP (JJ horizontal) (NNS layers))) (. .)))
When sediments settle out of water, they form horizontal layers.