人教版 必修4 Unit2Working the land Using language 课件（共17张）

课件17张PPT。Unit 2 Working the land
Using language safe food green food≈ organic food safe or not ?growing crops with natural fertilizers rather than chemical fertilizersSkimming:
What is ?
organic farmingScanning（group work）:Why are natural fertilizers better?
What problems are caused by using
chemical fertilizers?
3. What special ways of farming do
organic farmers use?
4. Why do the farmers do so?Why are natural fertilizers better?
2. What problems are caused by using
chemical fertilizers?Scanning（group work）:Use natural fertilizers. To make the soil richer.
Change crops every 2 To prevent the soil from
or 3 years. getting exhausted.
Grow crops that need To prevent wind or water
different levels of the from carrying away the
soil in between. soil.
3. What special ways of farming do organic farmers use?There is a big piece of field near your school.
The school is planning to grow some green food
in the field.
Make a plan with your group members:What green food to grow and why?
How to develop the soil?
What special ways to grow it?
What special ways to take care of your crop?Suppose:Make a poster（海报）: tell people what you are selling
make people believe your food is
good enough
persuade people to buy your food
make your poster as attractive as
possibleHomework:1. Design your posters and make
them more attractive.
2. Sum up what you have learned in
this unit, including useful words,
expressions and new grammar item.Organic farmingA summary (概括) of organic farming: no use of chemical fertilizers
away from industrial areas
away from dirty water supply
no air pollution
some special ways of farming to use
the food should be healthy and safe吃动物怕激素；吃植物怕毒素；
喝饮料怕色素；能吃什么，心里没数。
－－－全国人大代表金志国
带到两会上的顺口溜A quiz:Organic food just refers to vegetables and fruits.
Green food has a color of green.
Green food is certain to be healthy and safe.
Organic food is free of chemical fertilizers.
Organic food is grown away from dirty water supply.
Green food can be grown around big paper factories.