人教版（新课程标准）必修4Unit 2 Working the land Reading 课件（22张ppt）

(共22张PPT)
Chemical Or Organic Farming
First, buy or select the seeds from the store.
Second, we need to plow（犁田） or turn over the soil.
Third , we sow the seeds in the soil.
Finally, we can harvest our grain.
fertilize the soil
to increase production of the crops
fertilizer
fertilizer
How many kinds of fertilizers do you know
chemical fertilizers natural fertilizers
chemical farming organic farming
chemical fertilizers natural fertilizers
Better？
Reading
Chemical Or Organic Farming
Part 2
Part 1
Para 1.
Para 2.
Para 3.
Para 4.
Long-term use of___________ fertilizers can cause damage to_______________________.
Skim the text, try to get the main idea of each paragraph
Farmers and customers turn to_______________.
__________ caused by chemical fertilizers.
Other methods to keep_____________.
chemical
the land and people’s health
Problems
organic farming
the soil fertile
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Questions
1. Why are chemical fertilizers so popular in farming today
2. What is organic farming
Because they are a great way to stop crop disease and increase production.
Organic farming is farming without using any chemicals.
Read Part 1, try to find the problems and causes of chemical farming, then fill the blanks.
Problems Causes
Chemical farming
damage_________
affect ______, ______ and _________.
lead to ______ and ____________.
fruit, vegetables and other food have less ________.
by killing __________________ _______________________
by staying in the ground and
underground water
by building up_______________ _____________
by growing too fast
the land
crops animals
humans
cancer
other illness
nutrition
the helpful bacteria and pests as well as harmful ones.
in people’s bodies over time
Read Part 2, try to find the methods and advantages of organic farming as well as the way to keep the soil fertile, then fill the blanks.
Organic farming
Methods
use natural waste ____ ___________________
make the soil_______________ ______________________
change ______________ ____________________
put ________________ back into _______, making ____________ __________
plant different _____ with different lengths of _____
Use different levels of soil
plant _______________ and then leave it ______ __________
prevent wind or water from carrying away the soil and become a natural fertilizer
richer in minerals and so more fertile
from animals as fertilizer
the kind of crop in
each field every few years
important minerals the soil it ready for other crops
crops
roots
grass between crops
in the ground
Advantages
The methods to keep the soil fertile：
using natural waste from animals as fertilizer.
changing the kind of crop in each field .
planting crops to use different levels of soil.
planting grass between crops to prevent …
The same goal : ________________________
______________________________________
______________________________
to grow good food and avoid damaging the environment or people’s health.
1
2
3
4
In recent days, scientists have discovered that using________ fertilizers for a long time can _________________ the land and also people's health. There are several __________ caused by chemical fertilizers. They damage the land, stay in the water for a long time which can________ in people’s bodies and ____________ many illnesses.
chemical
problems
cause damage to
build up
Summary
lead to
________ farming is becoming more popular with some farmers. Organic farming does not use any chemicals and _________ keeping the soil rich. This also ______ the air and crops ___________ chemicals. There are many organic farming_________ for making the land healthy and productive. All of these methods try to produce good food and to keep the environment and people’s health.
keep
methods
focus on
Organic
free from
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.
Listening
What is the main topic of the conversation
　 The possible bad effects of chemical fertilizers on the fruit and vegetables that we eat today.
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.
True or False
Paul thinks that Carrie is not telling him the truth.
Using chemical fertilizers always makes vegetables empty inside.
Today’s fruit is not as healthy for people as fruit fifty years ago.
Eating more vegetables might not always be good for us.
All of today’s vegetables look healthy but in fact are not.
T
F
T
F
T
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Preview language points in Using Language part and finish the exercises on QuanChengSheJi.
Thank You!