( ( These ( drug ( education units ) ) ) ( ( ( ( lasted ( approximately 30 ) ) ( to ( 45 min ) ) ) ( over ( ( a period ) ( of ( ( ( 2 to ) 4 ) weeks ) ) ) ) ) . ) )
(ROOT (S (NP (DT These) (NN drug) (NN education) (NNS units)) (VP (VBD lasted) (NP (QP (RB approximately) (CD 30))) (PP (TO to) (NP (QP (CD 45) (CD min)))) (PP (IN over) (NP (NP (DT a) (NN period)) (PP (IN of) (NP (QP (CD 2) (TO to) (CD 4)) (NNS weeks)))))) (. .)))
These drug education units lasted approximately 30 to 45 min over a period of 2 to 4 weeks.
(ROOT (S (NP (DT The) (JJ fetal) (NN period)) (VP (VBZ lasts) (NP (NP (QP (RB approximately) (CD 30)) (NNS weeks)) (NP (NNS weeks)))) (. .)))