To make matters worse, the actual casing with all the little air vent holes amplifies the noise.

更糟糕的是，与所有的小空调通风孔实际套管的噪声放大。

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Casing air conditioning: indoor and outdoor machine are one, applicable to small area of the room, installing and cheaper prices.

窗式空调：室内外机合为一体，适用于小面积房间，安装方面且价格便宜。

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When the pump is first started, rotation of gears forces air out the casing and into the discharge pipe.

当泵首次启动时，齿轮的旋转迫使空气离开壳体进入排油管。

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In June, after U.S. investigators discovered the spent casing of a Russian-made surface-to-air missile lying in the desert near the Prince Sultan air base, Saudi intelligence arrested 11 Saudi members of an al-Qaeda cell for plotting to shoot down U.S. jets that use the facility and for preparing attacks against other American targets in the kingdom.

CNN: Do We Still Need the Saudis?