4. The Green Hills of Tangsa

5. Questions: What did Tangsa look like in the past? What does Tangsa look like at present?

6. no firewood Soil was ______ ____. carried away no trees In the past

7. At present Trees grow _____. thickly

8. At present People plant many trees __ ____ __ protect soil. in order to

9. TANGSATANGSA In the pastAt present No trees, no firewood Trees grow thickly Soil was carried away Roots fix soil together Trees were cut but none were planted. A few can be cut and the rest are left to grow even taller.

10. Uses of trees As a kind of fuel--firewood Building materials Homes(nest) of birds and wild animals … Give out oxygen & give food Prevent wind from blowing hard Make our world purer and more beautiful Prevent flood and keep air wet Provide a shade

12. storm breeze wind Stop wind from blowing hard and defend sand

13. Carbon dioxide CO 2 H2OH2O Water Oxygen O2O2 C n (H 2 O) m Carbon hydrate Photosynthesis （光合作用） Give out oxygen & supply food

14. water vapor Prevent flood Keep air wet rain water Absorbed by roots Evaporated( 蒸发 ) by leaves

15. Burn as firewood to warm us in winter

16. Provide a shade

17. Cherry blossom plum blossom pine willow maple Supply us beautiful environment ( 环境 )

18. According to the pictures below, please describe the environment around you, and point out the disasters or harm without trees!

20. Make full use of your imagination to put on a performance Key: show and emphasize the importance of trees to our life.

21. sky … air … mountain … winter … summer … city … house …