与美国小学生一起学英文第7册 第26期:八边形(在线收听

   Octagon 八边形

  What is a shape that has 5 lines and 5 angles? 哪种形状有五条边和五个角?
  It is a pentagon. 它就是五边形。
  What is a shape that has 8 lines and angles? 哪种形状有八条边和八个角呢?
  It is an octagon. 它就是八边形。
  "Oct" means "eight" and "gon" means "shape". “Oct”是“八”的意思,“gon”是“形状”的意思。
  Do you know what all the angles of an octagon add up to? 你知道八边形的内角和是多少吗?
  They add up to 1080 degrees. 它的内角和为1080度。
  A regular octagon has 8 lines all of the same length and all 8 angels are equal. 正八边形的八条边和八个角都相等。
  Where can you find octagon shape of things? 你在哪里能找到八边形的物体?
  How about your ball-pens or pencils? 圆珠笔或铅笔怎么样啊?
  They are all octagons. 它们都是八边形。
  Also, umbrellas and stop signs are octagons. 伞和停车标记也是八边形。
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