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- Guards patrolled the perimeter of the airfield. 卫兵沿机场四周巡逻。
- The perimeter of the airfield is protected by guard-dogs. 机场外的环形防卫圈由警犬保卫着。
- A fence marked the perimeter of the field. 一道篱笆标明了那块田地的周界。
- Work out how long the perimeter of the playground. 请你算一算体育场的周长是多少米?
- Guards patrol the perimeter of the estate. 保安人员在庄园四周巡逻。
- The river marks the eastern perimeter of our land. 这条河标示我们的土地东面的边界。
- Teacher: What is the perimeter of a circle? 师：什么是圆的周长?
- What is the perimeter of this oblong. （这个矩形的周长是多少?）
- perimeter of airway 风巷周长
- What is the perimeter of this polygon? 这个多边形的周长是多少?
- Observe for signs of airway obstruction. 观察气道梗阻体症。
- The perimeter of the airfield is protected by guard- dogs. 机场外的环形防卫圈由警犬保卫着。
- The perimeter of the airfield is protected by guard - dogs. 机场外的环形防卫圈由警犬保卫着。
- The perimeter of rectangle is the distance around it. 长方形的周长是指它边长的总合。
- Function of airways; Artificial respiration. 呼吸道的功能；人工呼吸。
- Count the perimeter of the following oblongs and squares. 求下面长方形和正方形的周长。
- Drinks in hands, they wandered around the perimeter of the ball field. 他们手里拿着饮料在球场周围漫不经心地遛跶。
- Teacher: Express the way of calculating the perimeter of a circle by letters. 师：圆的周长的计算方法，用字母公式表示。
- I can see better around the perimeter of my vision than in the middle. 我视野周围的比中央的看得清楚。
- This typically occurs prior to the secure perimeter of an Olympic venue. 典型安检是在进入奥运场馆的安全区前。
