About 20 minutes later, at 7:35, another passenger for Flight 77, Hani Hanjour, placed two carry-on bags on the X-ray belt in the Main Terminal's west checkpoint, and proceeded, without alarm, through the metal detector.
( ( ( ( About 20 ) minutes ) later ) ( , ( ( at 7:35 ) ( , ( ( ( ( ( ( another passenger ) ( for ( Flight 77 ) ) ) , ) ( Hani Hanjour ) ) , ) ( ( ( ( ( ( ( placed ( two ( carry-on bags ) ) ) ( on ( the ( X-ray belt ) ) ) ) ( in ( ( the ( Main ( Terminal 's ) ) ) ( west checkpoint ) ) ) ) , ) and ) ( ( ( ( proceeded , ) ( without alarm ) ) , ) ( through ( the ( metal detector ) ) ) ) ) . ) ) ) ) ) )
(ROOT (S (ADVP (NP (QP (RB About) (CD 20)) (NNS minutes)) (RB later)) (, ,) (PP (IN at) (NP (CD 7:35))) (, ,) (NP (NP (NP (DT another) (NN passenger)) (PP (IN for) (NP (NNP Flight) (CD 77)))) (, ,) (NP (NNP Hani) (NNP Hanjour)) (, ,)) (VP (VBD placed) (NP (CD two) (JJ carry-on) (NNS bags)) (PP (IN on) (NP (DT the) (NN X-ray) (NN belt))) (PP (IN in) (NP (NP (DT the) (NNP Main) (NNP Terminal) (POS 's)) (JJ west) (NN checkpoint)))) (, ,) (CC and) (VP (VBD proceeded) (, ,) (PP (IN without) (NP (NN alarm))) (, ,) (PP (IN through) (NP (DT the) (NN metal) (NN detector)))) (. .)))
While passing through the checkpoint, Hani set off several alarms.
( ( While ( passing ( through ( the checkpoint ) ) ) ) ( , ( Hani ( ( ( set off ) ( several alarms ) ) . ) ) ) )
(ROOT (S (SBAR (IN While) (S (VP (VBG passing) (PP (IN through) (NP (DT the) (NN checkpoint)))))) (, ,) (NP (NNP Hani)) (VP (VBD set) (PRT (RP off)) (NP (JJ several) (NNS alarms))) (. .)))