loudness什么意思解释？

loudness的音标：loudness的英式发音音标为：[laʊdnəs]loudness的美式发音音标为：['laʊdnɪs]...

The amplitude of the vibration determines the loudness of the sound.振动幅度的大小决定声音的大小.The students began to enter the classroom and Anna was startled at their loudness.学生们开始进入教室.安娜被他们的喧闹声吓了一跳.His heart bumped in his breast ...