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美国纽约市、洛杉矶市等地的消防人员,都随身带有一种自动报警呼救牌,卡在皮带上,或装在口袋里。呼救牌有颗小金属
Firefighters in places like New York City and Los Angeles in the United States all carry an automatic wake-up call card, stuck on a belt or in a pocket. For help card has a small metal