The study was undertaken using a sound level meter operated by a passenger in each car tested.

研究用这样的方式进行：每辆接受测试的汽车的乘客开启声音强度测试仪。

youdao

The study was undertaken using a sound level meter operated by a passenger in each car tested.

研究用这样的方式进行：每辆接受测试的汽车的乘客开启声音强度测试仪。

youdao