( I ( ( have ( lost ( ( the ( knee ( jerk reflex ) ) ) ( in ( the ( left leg ) ) ) ) ) ) . ) )
(ROOT (S (NP (PRP I)) (VP (VBP have) (VP (VBN lost) (NP (NP (DT the) (NN knee) (NN jerk) (NN reflex)) (PP (IN in) (NP (DT the) (JJ left) (NN leg)))))) (. .)))
I have lost the knee jerk reflex in the left leg.
(ROOT (X (NP (DT The) (`` ``) (JJ knee-jerk) ('' '') (NN motion)) (SBAR (IN that) (S (NP (NNS people)) (ADVP (RB involuntarily)) (VP (VBP perform) (SBAR (IN after) (S (S (VP (VBG being) (VP (VBN struck) (PP (IN in) (NP (NP (DT the) (NN knee)) (PP (IN in) (NP (DT a) (JJ certain) (NN way)))))))) (VP (VBZ is) (NP (NP (DT an) (NN example)) (PP (IN of) (NP (DT a) (JJ reflex))))))))))))