( ( A foal ) ( normally ( ( ( ( takes ( ( 20 breaths ) ( a minute ) ) ) , ) ( while ( ( an adult ) ( breathes ( only ( 12 times ) ) ) ) ) ) . ) ) )
(ROOT (S (NP (DT A) (NN foal)) (ADVP (RB normally)) (VP (VBZ takes) (NP (NP (CD 20) (NNS breaths)) (NP (DT a) (NN minute))) (, ,) (SBAR (IN while) (S (NP (DT an) (NN adult)) (VP (VBZ breathes) (NP (QP (RB only) (CD 12) (NNS times))))))) (. .)))
A foal normally takes 20 breaths a minute, while an adult breathes only 12 times.
(ROOT (S (NP (NP (DT The) (JJ normal) (NN respiratory) (NN rate)) (PP (IN per) (NP (NP (NN minute)) (PP (IN in) (NP (JJ adult) (NNS humans)))))) (VP (VBZ is) (NP (CD 12-18) (NNS breaths))) (. .)))