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德国人发明了一种新型牙膏,这种牙膏装在一个特别的泵自动挤压器里,泵的基本组成部分包括一个刚性塑料罩,罩上带有一个插到底部的活塞,一个裹在颈部的柔性塑料锥和一个扣在顶部用来压牙膏的刚性塑料
The Germans invented a new type of toothpaste, which is housed in a special automatic pump pump. The basic components of the pump include a rigid plastic cover with a piston inserted into the bottom and a neck wrapped around the neck Department of the flexible plastic cone and buckle the top of the rigid plastic used to pressure toothpaste