( ( Within ( ( a matter ) ( of ( ( ( 10 to ) 15 ) minutes ) ) ) ) ( , ( ( ( the pupil ) ( of ( the eye ) ) ) ( ( opens ( to ( approximately 7mm ) ) ) . ) ) ) )
(ROOT (S (PP (IN Within) (NP (NP (DT a) (NN matter)) (PP (IN of) (NP (QP (CD 10) (TO to) (CD 15)) (NNS minutes))))) (, ,) (NP (NP (DT the) (NN pupil)) (PP (IN of) (NP (DT the) (NN eye)))) (VP (VBZ opens) (PP (TO to) (NP (QP (RB approximately) (CD 7mm))))) (. .)))
Within a matter of 10 to 15 minutes, the pupil of the eye opens to approximately 7mm.
(ROOT (S (NP (DT The) (NN pupil)) (VP (VBZ is) (NP (NP (DT the) (NN opening)) (PP (IN in) (NP (NP (DT the) (NN front)) (PP (IN of) (NP (DT the) (NN eye))))))) (. .)))