Green world教案
let’s take dandelions as an example.they are widespread and can be found almost everywhere.their yellow flowers are beautiful and their leaves look like the teeth on a saw.the wind spread their flowers and seeds everywhere,so when they grow in hot and dry places,they are low and thin.their flowers and leaves are short and light in colour,5-10 centimetres long.they grow close to the ground and their roots are deep in it.their hearts are a little sunken into the earth,so that the rain water can flow from the leaves to the heart where the roots are.
but in places it is cool and wet,things are different.they become higher and stronger and can grow as long as 15-20 centimetres.their leaves are broader and their flowers are larger.the colour of the flowers and leaves becomes darker green.if some weeds are taken here,there will be many of them a few weeks later.
a great swedish scientist gote turesson said that differences between plants of one species occured as a result of the environmental conditions in their habitat.from dandelions we can see this clearly.
step ⅵ the design of the writing on
the blackboard
unit 4 green worlds
the fouth period
what can we learn from the text?
step ⅶ record after teaching
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