The filming of the machine room door ventilation grille is to get the sound of the powertrain inside, but nothing can be heard from this.

当中拍摄机房门的通风格栅，目的是要拮取里面驱动机芯的声音，但最终并不能由此听到任何有关的声音。

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The mouthpiece of the suction machine attached to the Dredge Carolina has been fitted with a grille to keep it from swallowing large munitions, but that means pieces of trash get caught, and someone has to remove debris every three hours.

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