The loudspeaker announced each airplane as it landed at the airport.

每架飞机在机场一着陆, 扩音就发出通告。

He gave a tap at the microphone before speaking.

他在讲前先轻叩了一下扩音。

He used a microphone so that everyone could hear him.

"他使用扩音,使人人都能听见他的讲。"

The Mega-Sonic Scatter-Cat Repeller looks like a megaphone because it actually is one.

超音波驱猫上去像扩音，它的确是的。

Amplifier is electrical device which make sounds louder.

扩音是一种使声音放大的电气装置。

SASHED candidates standing on car roofs, their voices crackling through loudspeakers.

候选人从车顶的窗口探出头来，扩音下他的嗓音略微嘈杂。

All the speakers hook up to a single amplifier.

所有喇叭都接在单一的扩音上。