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[lemma=the] [□] □ □
[lemma=the] □ □ □ □
During the trips a group of students , dubbed a task force , inspects a city neighborhood in transition and talks with people living and working in the area . On one of the trips a wheel came off one of the wagons , though the accident turned out to be not-so-serious . The second mechanism specifically mentioned is a number limit on the trips a passenger can take in a given period of time .