( ( Simple ( Machines ( Sort Mail ) ) ) ( ( Describes ( ( the use ) ( of ( ( simple machines ) ( in ( sorting mail ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Simple) (NNPS Machines) (NNP Sort) (NNP Mail)) (VP (VBZ Describes) (NP (NP (DT the) (NN use)) (PP (IN of) (NP (NP (JJ simple) (NNS machines)) (PP (IN in) (NP (VBG sorting) (NN mail))))))) (. .)))
Simple Machines Sort Mail Describes the use of simple machines in sorting mail.
(ROOT (S (S (NP (DT A) (JJ complex) (NN machine)) (VP (VBZ is) (VP (VBN described) (PP (IN by))))) (: :) (S (NP (PRP it)) (VP (VBZ is) (VP (VBN made) (PP (IN of) (NP (QP (JJR more) (IN than) (CD one)) (JJ simple) (NN machine)))))) (. .)))
A complex machine is described by: it is made of more than one simple machine.