I jumped, coat tails flapping.
( I ( ( ( jumped , ) ( ( coat tails ) flapping ) ) . ) )
(ROOT (S (NP (PRP I)) (VP (VBD jumped) (, ,) (S (NP (NN coat) (NNS tails)) (VP (VBG flapping)))) (. .)))
I jumped while wearing a coat.
( I ( ( jumped ( while ( wearing ( a coat ) ) ) ) . ) )
(ROOT (S (NP (PRP I)) (VP (VBD jumped) (SBAR (IN while) (S (VP (VBG wearing) (NP (DT a) (NN coat)))))) (. .)))