扩音器 /kuòyīnqì/ angolul

loudspeaker [loudspeakers]▼(transducer)
noun
[UK: laʊd.ˈspiːkə(r)] [US: ˈlaʊd.ˌspikər]

megaphone [megaphones]▼(portable device used to amplify a person's voice)
noun
[UK: ˈme.ɡə.fəʊn] [US: ˈme.ɡəˌfoʊn]