海岸从两边伸展开去，海岬紧接着海岬，你看得见海岬尖端海浪冲在岩石上溅起的白色泡沫，声音可听不到了，因为距离太远了。
On either hand the coast stretched away, headland after headland, and at the points you could see the white foam running up the rocks but making no noise because it was so far off.
距离 1 米处可听噪声不超过 70 分贝，满足试验室现场要求。
The noise of system with 1 meter distance could be below 70 dB, satisfy the lab working area requirement.
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