The arches that flank the nave are filled with tiers of columns and the walls with windows, while the arches above the entrance and the apse are backed by semi-domes, further increasing the interior space.
( ( ( The arches ) ( that ( flank ( the nave ) ) ) ) ( ( are ( ( ( ( filled ( with ( tiers ( of ( ( columns and ) ( the walls ) ) ) ) ) ) ( with windows ) ) , ) ( while ( ( ( the arches ) ( above ( ( ( the entrance ) and ) ( the apse ) ) ) ) ( are ( ( ( backed ( by semi-domes ) ) , ) ( further ( increasing ( the ( interior space ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NNS arches)) (SBAR (WHNP (WDT that)) (S (VP (VBP flank) (NP (DT the) (NN nave)))))) (VP (VBP are) (VP (VBN filled) (PP (IN with) (NP (NP (NNS tiers)) (PP (IN of) (NP (NP (NNS columns)) (CC and) (NP (DT the) (NNS walls)))))) (PP (IN with) (NP (NNS windows))) (, ,) (SBAR (IN while) (S (NP (NP (DT the) (NNS arches)) (PP (IN above) (NP (NP (DT the) (NN entrance)) (CC and) (NP (DT the) (NN apse))))) (VP (VBP are) (VP (VBN backed) (PP (IN by) (NP (NNS semi-domes))) (, ,) (S (ADVP (RB further)) (VP (VBG increasing) (NP (DT the) (JJ interior) (NN space)))))))))) (. .)))
Thr arches that flank the nave are in the best condition of all the arches.
( Thr ( ( arches ( that ( flank ( ( the nave ) ( are ( in ( ( the ( best condition ) ) ( of ( all ( the arches ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Thr)) (VP (VBZ arches) (SBAR (IN that) (S (VP (VBP flank) (SBAR (S (NP (DT the) (NN nave)) (VP (VBP are) (PP (IN in) (NP (NP (DT the) (JJS best) (NN condition)) (PP (IN of) (NP (PDT all) (DT the) (NNS arches)))))))))))) (. .)))