第十五课

  The three state changes of water水的三态变化

1. A tiny drop of water, which turns into crystal ice crystals in cold weather.一滴小小的水珠，在寒冷的天气里会变成晶莹的冰晶；

2. Under the sun, without realizing it, the ice crystal melts and disappears.在太阳的照射下，不知不觉中，冰晶就会融化并消失。

3. Where does it go?它去哪儿了？

4. Where can we look for it?在哪里能寻找到它的踪迹？

15  Water evaporates水蒸发

1. When it rains, the water on the road is invisible after a while.雨过天晴，马路上的水过一段时间就看不见了。

2. Why is this?这是为什么呢？

3. Material package: towel, small fan, etc.材料包：毛巾，小风扇等。

4. Activity process活动过程

5. Where does the water go?水到哪里去了？

6. thought navigation思维导航

7. Where did the water "run" to?水“跑”到哪里去了？

8. Can you see the water when it is running?水“跑”的时候，你能看见吗？

9. what does this mean?这说明什么？

10. Water vapor is a colorless, odorless, tasteless, transparent gas.水蒸气是没有颜色、没有气味、没有味道、透明的气体。

11. The phenomenon of water slowly turning into water vapor and flying into the air is called evaporation.水慢慢变成水蒸气飞散到空气中的现象叫做蒸发。

12. In summer, why do you feel cool when you first get out of the swimming pool?夏天，刚从游泳池出来时为什么感觉到凉？

13. I guess water evaporates when ------我猜想水蒸发时会······

14. Rub water on your hands and try it out.把水擦到手上试一试。

15. I feel ----我感觉······

16. Use a water thermometer to measure it.用水温计测一测。

17. Did the temperature change?温度有变化吗？

18. method guide方法指导

19. Wrap the glass bubble of the water thermometer with gauze and observe the temperature.用纱布包住水温计的玻璃泡，观测温度。

20. Put the water thermometer in water (room temperature) and soak the gauze.将水温计放入水（室温）中，浸湿纱布。

21. Stand for a period of time.静置一段时间，

22. Record the temperature after the column of liquid has stood still.液柱静止不动后记录温度。

23. Remove the water thermometer from the water.将水温计从水中取出，

24. Observe the change in the liquid column and make a record.观察液柱的变化，做好记录。

25. The water evaporates, the temperature around it decreases.水蒸发时会使周围的温度降低。

26. How to make the water evaporate faster?怎样让水蒸发的更快？

27. After heating for a while ------加热一段时间后······

28. An unfolded towel is better than a folded towel ------展开的毛巾比叠起的毛巾······

29. I still have a solution ------我还有办法······

30. extension activity拓展活动

31. Learn how water evaporation relates to our lives.了解水的蒸发与我们生活的关系。