While traveling 35,000 feet above eastern Ohio, United 93 suddenly dropped 700 feet.
( ( While ( traveling ( ( 35,000 feet ) ( above ( eastern Ohio ) ) ) ) ) ( , ( ( United 93 ) ( suddenly ( ( dropped ( 700 feet ) ) . ) ) ) ) )
(ROOT (S (SBAR (IN While) (S (VP (VBG traveling) (NP (NP (CD 35,000) (NNS feet)) (PP (IN above) (NP (JJ eastern) (NNP Ohio))))))) (, ,) (NP (NNP United) (CD 93)) (ADVP (RB suddenly)) (VP (VBD dropped) (NP (CD 700) (NNS feet))) (. .)))
The plane began to increase its altitude rapidly.
( ( The plane ) ( ( began ( to ( ( increase ( its altitude ) ) rapidly ) ) ) . ) )
(ROOT (S (NP (DT The) (NN plane)) (VP (VBD began) (S (VP (TO to) (VP (VB increase) (NP (PRP$ its) (NN altitude)) (ADVP (RB rapidly)))))) (. .)))