Surrounding the end of the stomach is a ringlike muscle called pyloric valve.
圍繞在胃末端的是一片環(huán)狀肌肉叫做幽門瓣.
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Each ball bearing has three main parts: two grooved , ringlike races and a number of balls.
球軸承有三個主要零件, 即 兩個帶有溝槽的套圈和許多球.
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