第二十课

20  The position of an object in motion物体运动的位置

1. How do you describe your position to others when you are on the way out?外出途中，你是怎样向他人描述自己所处的位置的？

2.  Material package: watch材料包：手表

3. Activity process活动过程

4.  How to determine that an object is in motion?怎样判断物体是运动的？

5. Using the starting line as a reference ------以起跳线为参照······

6. My position has changed relative to the starting line.我的位置相对于起跳线发生了变化。

7. Describe the change in their position.描述他们位置的变化。

8. By the motion of an object we mean that the position of one object has changed relative to another object.我们所说的物体的运动是指一个物体相对于另一个物体来说位置发生了变化。

9. To determine whether an object is in motion, the要判断一个物体是否在运动，

10.  It is necessary to choose another object as a standard, the需要选择另一个物体作为标准，

11.  This object used as a standard is called a reference object.这个作为标准的物体叫参照物。

12. Describe the position of a moving object at a given moment.描述运动物体在某一时刻的位置。

13. At 10:15, Xiaohong is south of Xiaoming, a distance from Xiaoming ------10时15分，小红在小明的南方，距离小明······

14. Method guide方法指导

15. The position of Xiaoming remains the same.小明的位置不变。

16. Xiaohong walks with a timing tool following a certain route小红带着计时工具按照一定路线行走，

17.  While walking, report the moment and his direction relative to Xiaoming.边走边报出时刻和自己相对小明的方向，

18. Report every other time.每隔一段时间报一次。

19. Measure the distance between Xiao Hong and Xiao Ming at the corresponding moment.测出相应时刻小红与小明的距离。

20. The position of a moving object at a moment in time that运动物体在某一时刻的位置，

21.  can be described by the direction and distance relative to a reference object.可以用相对于参照物的方向和距离来描述。

22. Describe the relative positions of two moving objects at a given moment.描述两个运动物体在某一时刻的相对位置。

23.  Now she is in front of my left, about ------ away from me现在她在我的左前方，距离我约······

24.  Extend the activity拓展活动

25. Learn to use modern tools to orient yourself.学习使用现代化工具给自己定位。