At 9:03:11, United Airlines Flight 175 struck the South Tower of the World Trade Center.
( ( At 9:03:11 ) ( , ( ( United ( Airlines ( Flight 175 ) ) ) ( ( struck ( ( the ( South Tower ) ) ( of ( the ( World ( Trade Center ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN At) (NP (CD 9:03:11))) (, ,) (NP (NNP United) (NNP Airlines) (NNP Flight) (CD 175)) (VP (VBD struck) (NP (NP (DT the) (NNP South) (NNP Tower)) (PP (IN of) (NP (DT the) (NNP World) (NNP Trade) (NNP Center))))) (. .)))
United Airlines Flight 175 struck the North Tower at 9:05:15.
( ( United ( Airlines ( Flight 175 ) ) ) ( ( ( struck ( the ( North Tower ) ) ) ( at 9:05:15 ) ) . ) )
(ROOT (S (NP (NNP United) (NNP Airlines) (NNP Flight) (CD 175)) (VP (VBD struck) (NP (DT the) (NNP North) (NNP Tower)) (PP (IN at) (NP (CD 9:05:15)))) (. .)))