( ( According ( to Ashbaugh ) ) ( , ( ( the fingerprints ) ( ( begin ( forming ( on ( ( the fetus ) ( around ( ( the ( thirteenth week ) ) ( of development ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (VBG According) (PP (TO to) (NP (NNP Ashbaugh)))) (, ,) (NP (DT the) (NNS fingerprints)) (VP (VBP begin) (S (VP (VBG forming) (PP (IN on) (NP (NP (DT the) (NN fetus)) (PP (IN around) (NP (NP (DT the) (JJ thirteenth) (NN week)) (PP (IN of) (NP (NN development)))))))))) (. .)))
According to Ashbaugh, the fingerprints begin forming on the fetus around the thirteenth week of development.
(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.