They change sugar into acids, which break down the tooth's harder outer covering.

它们把糖转化成酸，酸会腐蚀较硬的牙齿外层。

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They are to carry the curtains of the tabernacle, the Tent of Meeting, its covering and the outer covering of hides of sea cows, the curtains for the entrance to the Tent of Meeting.

他们要抬帐幕的幔子和会幕，并会幕的盖，与其上的海狗皮和会幕的门帘。

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Language is the physical outer covering of thought. The linguistic organization and expression are restricted by logic.

语言是思维的物质外壳，语言的组织和表达都要受逻辑的制约。

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Approximately 30 percent of the cottonseed's weight is in the hull, or outer covering.

NPR: Texas Cotton: 'Farmer Profits at Every Step'

The husk, the outer covering of the barley grain, is placed in a bi-fermentor which transforms the cellulose into methane gas.

CNN: Brewing giant Carlsberg's sustainability drive pays off

The outer covering was a windproof and water resistant shell.

FORBES: Sleeping Softly on the Roof: Sleeping Bag Reviews