amp.

例句：

1. 1. The engineer used an amp to amplify the sound of the music.
   工程师使用一个放大器来增强音乐的声音。
2. 2. The company has been using amps to improve its product quality.
   该公司一直在使用放大器来提高其产品的质量。
3. 3. The amp was designed to amplify the signal from the microphone.
   这个放大器被设计用来放大麦克风的信号。