( ( For example ) ( , ( ( ( a ( male 's ) ) genes ) ( ( would ( begin ( to ( show ( ( the fetus ) ( as ( ( male ( -LRB- ( ( usually ( about ( 7 weeks ) ) ) -RRB- ) ) ) ( by ( developing ( testicles ( , ( ( scrotum and ) penis ) ) ) ) ) ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN For) (NP (NN example))) (, ,) (NP (NP (DT a) (NN male) (POS 's)) (NNS genes)) (VP (MD would) (VP (VB begin) (S (VP (TO to) (VP (VB show) (NP (NP (DT the) (NN fetus)) (ADJP (RB as) (NN male) (PRN (-LRB- -LRB-) (PP (ADVP (RB usually)) (IN about) (NP (CD 7) (NNS weeks))) (-RRB- -RRB-)) (PP (IN by) (S (VP (VBG developing) (NP (NNS testicles) (, ,) (NN scrotum) (CC and) (NNS penis)))))))))))) (. .)))
For example, a male's genes would begin to show the fetus as male (usually about 7 weeks) by developing testicles, scrotum and penis.
(ROOT (S (NP (NP (DT The) (NN development)) (PP (IN of) (NP (NP (DT the) (JJ respiratory) (NN system)) (PP (IN in) (NP (DT the) (NN fetus)))))) (VP (VBZ begins) (PP (IN at) (NP (QP (RB about) (CD 4)) (NNS weeks)))) (. .)))
The development of the respiratory system in the fetus begins at about 4 weeks.