Citizens of Parktown are worried by the increased frequency of serious crimes committed by local teenagers  In response, the city government has instituted a series of measures designed to keep teenagers at home in the late evening  Even if the measures succeed in keeping teenagers at home, however, they are unlikely to affect the problem that concerns citizens, since most crimes committed by local teenagers take place between 3 p  m  and 6 p
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Teenagers are much less likely to commit serious crimes when they are at home than when they are not at home.