21.   According to Gaudio, Anita told Sana that she had been in the trade center when the first plane hit.

22.   After billowing soot and ash blacked out his floor-to-ceiling windows, he felt Liberty Tower sway and realized that the trade center had collapsed.

23.   After Parrino dropped off their children at a Midtown Manhattan school, he heard the news and pointed himself toward the trade center.

24.   Against his better judgment, he has become a devotee of the trade center and its below-the-radar operations.

25.   After the first plane rammed the trade center last week, he called a close friend to say that he was on the street and was all right.

26.   Agency officials were further mortified when two of the hijackers received their student visas to attend flight schools six months after ramming jetliners into the trade center.

27.   Both towers of the trade center crumbled and several adjoining buildings collapsed or were severely damaged.

28.   But he asked to be sent to the trade center, because of his training as a paramedic.

29.   But most of the casualties were believed to be in the rubble of the trade center.

30.   But one, which was apparently outside the trade center when the planes hit, was a striking reminder of the lives lost.