( ( ( ( ( Some machines ) , ) ( such ( as bicycles ) ) ) , ) ( ( are ( complex ( because ( they ( involve ( ( more ( than one ) ) ( simple machine ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT Some) (NNS machines)) (, ,) (PP (JJ such) (IN as) (NP (NNS bicycles))) (, ,)) (VP (VBP are) (ADJP (JJ complex) (SBAR (IN because) (S (NP (PRP they)) (VP (VBP involve) (NP (QP (JJR more) (IN than) (CD one)) (JJ simple) (NN machine))))))) (. .)))
Some machines, such as bicycles, are complex because they involve more than one simple machine.
(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.