91：1
美 [ˌnaɪn wʌn ˈwʌn]英 [.naɪn wʌn 'wʌn]
91：191：1
1.in the U.S., the telephone number that you use in an emergency to call the police, the fire department, or an ambulance
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91：191：11.in the U.S., the telephone number that you use in an emergency to call the police, the fire department, or an ambulance