( ( A watershed ) ( ( is ( ( ( an area ) ( of land ) ) ( that ( ( ( is ( drained ( by ( a ( distinct ( stream ( or ( river system ) ) ) ) ) ) ) ) and ) ( is ( ( separated ( from ( other watersheds ) ) ) ( by ( ridge ( top boundaries ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT A) (NN watershed)) (VP (VBZ is) (NP (NP (DT an) (NN area)) (PP (IN of) (NP (NN land))) (SBAR (WHNP (WDT that)) (S (VP (VP (VBZ is) (VP (VBN drained) (PP (IN by) (NP (DT a) (JJ distinct) (NN stream) (CC or) (NN river) (NN system))))) (CC and) (VP (VBZ is) (VP (VBN separated) (PP (IN from) (NP (JJ other) (NNS watersheds))) (PP (IN by) (NP (JJ ridge) (JJ top) (NNS boundaries)))))))))) (. .)))
A watershed is an area of land that is drained by a distinct stream or river system and is separated from other watersheds by ridge top boundaries.
(ROOT (S (NP (NP (DT All)) (PP (IN of) (NP (NP (DT the) (NN land)) (VP (VBN drained) (PP (IN by) (NP (DT a) (NN river) (NN system))))))) (VP (VBZ is) (VP (VBN called) (NP (NP (PRP$ its) (NN basin)) (, ,) (CC or) (NP (DT the) (`` ``) (JJ wet) ('' '') (NN term) (NN watershed)))))))