( ( Fetuses ( infected ( between ( 4-6 months ) ) ) ) ( frequently ( ( develop ( ( malformations , ) ( including ( ( eye and ) ( central ( nervous ( system abnormalities ) ) ) ) ) ) ) . ) ) )
(ROOT (S (NP (NP (NNS Fetuses)) (VP (VBN infected) (PP (IN between) (NP (CD 4-6) (NNS months))))) (ADVP (RB frequently)) (VP (VBP develop) (NP (NP (NNS malformations)) (, ,) (PP (VBG including) (NP (NP (NN eye)) (CC and) (NP (JJ central) (JJ nervous) (NN system) (NNS abnormalities)))))) (. .)))
Fetuses infected between 4-6 months frequently develop malformations, including eye and central nervous system abnormalities.
(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.