The first Merlefest,held in 1988, attracted just 4,000 fans who gathered to watch Merle's friends jamming on a few flatbed trucks.

VOA: standard.2010.06.07

So then to encourage you to "Pump up your room" they had music playing and this is the kind of music that they had on that flatbed truck.

然后还鼓动你去"律动你的房间",他们还放着音乐,这就是他们在那辆卡车上播放的音乐类型

耶鲁公开课 - 聆听音乐课程节选

There was a large flatbed truck out there and there were these people on this truck getting you-- trying to sell you audio equipment, and they had a big banner up there.

那儿有一个大平板卡车,有一群人在车上,正试图向你推销音响,他们还有个巨大的横幅

耶鲁公开课 - 聆听音乐课程节选