local Mach number

例句：

1. 1.The local government is considering a new law to protect the environment.
   当地政府正在考虑一项新的法律来保护环境。
2. 2. The local economy has been struggling due to the pandemic.
   由于疫情，当地经济一直很困难。
3. 3. The locals are known for their friendly and welcoming nature.
   当地人以友好和热情著称。