人教版高一上册英语必修4课件《Unit2 Working the land Using Language》（45张）

(共45张PPT)
高一必修4
Using
Language
Unit
2
Working
the
land
discovery
focus
soil
reduce
root
n.
发现；发觉
n.
焦点；中心点
vt.
集中；聚焦
n.
土壤
vt.
减少；减缩
n.
根；根源
chemical
production
bacteria
pest
nutrition
mineral
adj.
化学的；关于化学的
n.
生产；制造
n.
细菌
n.
害虫；害兽；害鸟
n.
营养；滋养；食物
n.
矿物；矿石
预习检测
build
up
lead
to
focus
on
keep…
free
from/of
逐渐增强;
建立;
开发
导致;
造成
(后果)
集中
(注意力，精力等)
于
使…免受(影响，伤害等)；
使…不含(有害物)
What
are
genetically-modified
foods?
The
term
GM
foods
or
GMOs
(genetically-modified
organisms)
is
most
commonly
used
to
refer
to
crop
plants
created
for
human
or
animal
consumption
using
the
latest
molecular
biology
techniques.
新课导入
1).pest
resistance
2).disease
resistance
3).cold
tolerance
4).drought
tolerance/salinity
tolerance
5).nutrition
What
are
some
of
the
advantages
of
GM
foods?
The
world
population
has
topped
6
billion
people
and
is
predicted
to
double
in
the
next
50
years.
Ensuring
an
adequate
food
supply
for
this
booming
population
is
going
to
be
a
major
challenge
in
the
years
to
come.
GM
foods
promise
to
meet
this
need
in
a
number
of
ways:
Chemical
or
organic
farming?
Main
idea
__________
farming
can
cause
many
problems,
so
_______
farming
is
becoming
more
popular.
It
means
growing
crops
without
chemical
__________which
damage
the
soil.
The
organic
farmers
keep
the
soil
rich
and
_______
in
four
ways.
organic
fertilizers
healthy/
fertile
Chemical
Skimming
1
Why
are
chemical
fertilizers
so
popular
in
farming
today?
2
What
problems
can
be
caused
by
using
chemical
fertilizers?
3
What
is
organic
farming?
4
What
is
the
main
reason
for
using
organic
farming
methods?
Read
the
passage
and
answer
the
following
questions.
1
Why
are
chemical
fertilizers
so
popular
in
farming
today?
They
are
a
great
way
to
stop
crop
disease
and
increase
production.
2
What
problems
can
be
caused
by
using
chemical
fertilizers?
They
can
damage
the
land
by
killing
helpful
bacteria
and
pets
and
by
staying
in
the
ground
and
underground
water
for
a
long
time,
They
damage
people's
health
by
building
up
in
their
bodies
and
leading
to
cancer
or
other
illnesses.
3
What
is
organic
farming?
4
What
is
the
main
reason
for
using
organic
farming
methods?
Organic
farming
means
growing
crops
without
using
any
chemicals.
The
main
reason
for
using
organic
farming
methods
is
to
grow
good
food
and
to
avoid
damaging
the
environment
or
people’s
health.
Scanning
Chemical
or
Organic
farming?
_________
Farming
_________
Farming
Para.
1
:
Para.
2:
Para.
3:
Para.
4:
Chemical
Organic
Problems
caused
by
chemical
fertilizers.
Farmers
and
customers
turn
to
organic
farming.
Other
methods
to
keep
the
soil
fertile.
Long-term
use
of
chemical
fertilizers
can
cause
damage
to
the
land
and
people’s
health.
Find
and
write
down
the
methods
and
advantages
in
the
passage.
Methods
of
organic
farming
Advantages
of
methods
Farmers
use
natural
waste
from
animals.
This
makes
the
soil
richer
in
minerals
and
so
more
fertile.
新课讲解
Methods
of
organic
farming
Advantages
of
methods
1
Farmers
use
natural
waste
from
animals.
1
This
makes
the
soil
richer
in
minerals
and
so
more
fertile.
2
Farmers
often
change
the
kind
of
crop
in
each
field
every
few
years.
2
Changing
the
crops
renews
the
minerals
in
the
soil
and
helps
it
become
rich
and
healthy.
Methods
of
organic
farming
Advantages
of
methods
3
Farmers
plant
crops
with
different
lengths
of
roots.
3
This
uses
different
levels
of
soil.
4
Farmers
sometimes
plant
grass
between
crops
and
leave
it
in
the
ground.
4
This
prevents
wind
or
water
from
carrying
away
soil
and
acts
as
a
natural
fertilizer.
Disadvantages
Although
chemical
farming
stop
crop
disease
and
increase
production,
Damaging
the
land:
killing
the
helpful
______
and
____
;
Damaging
people's
health;
Many
chemicals
in
the
food
supply
can
______
__
cancer
or
other
illnesses;
Food
grows
too
fast
to
be
full
of
much
_________.
Careful
reading
bacteria
pests
nutrition
lead
to
1.
build
up
(1)增多，加强，加大
①These
exercises
are
good
for
building
up
leg
strength.
这些锻炼有助于增强腿部的力量。
②Their
words
built
up
my
confidence.
他们的话增强了我的信心。
③My
stress
built
up
as
time
went
on.
随着时间的推移，我的压力越来越大。
知识探究
(2)建立，开发
④She’s
built
up
a
very
successful
business.
她创办的生意红红火火。
⑤We
built
up
this
business
after
ten
years’
struggle.
经过10年拼搏后我们建立了这家公司。
(3)增强……的体质；使更加强壮
⑥You
need
lots
of
fresh
fruit
to
build
you
up.
你得多吃新鲜水果以增强体质。
[即境活用]
完成句子
①我从10岁起就通过观看成千上万部英语影碟来增强我的英语水平。
I’ve________
________
________
________by
watching
thousands
of
English
DVDs
since
I
was
10.
②这将帮助科学家建立一个新的生物分支。
This
will
help
scientists________
________a
new
branch
of
biology.
答案：①built
up
my
English　②build
up
2.
lead
to
(1)导致，造成(后果)
①What
on
earth
led
to
so
many
mine
disasters?
到底是什么导致了这么多矿难？
②Eating
too
much
sugar
leads
to
much
weight.
吃太多的糖会导致增肥。
③Several
factors
led
us
to
choose
famous
universities
for
our
study.
几个因素促使我们选择名牌大学学习。
[归纳拓展]
lead
sb.to
some
place带领某人到某地
lead
sb.in
doing
sth.率领某人干某事
lead
one’s
/the
way带路，领路
(2)通向，通往
④The
path
leads
to
that
small
village.
这条小路通向那个小村子。
⑤All
roads
lead
to
Rome.(谚)条条大路通罗马。
[即境活用]
完成句子
①过量的工作和过少的休息会引发疾病。
Too
much
work
and
too
little
rest
often________
________
illness.
②你是如何得出这个结论的？
What________
________
________this
conclusion?
③是什么让你开始从事演艺事业的？
What________
________
________
________
________
acting
as
a
career?
答案：①leads
to　②led
you
to　③led
you
to
take
up
focus
on
(1)集中(注意力、精力等)于……；关注……
①All
eyes
were
focused
on
the
speaker.
大家的目光都集中在发言人身上。
②You
must
try
to
focus
your
mind
on
your
study.
你必须努力把心思用在学习上。
[归纳拓展]
focus
one’s
attention
/mind
on
/upon
集中注意力/心思于
concentrate
on
sth.集中(注意力、精力等)于
pay
attention
to注意
put
one’s
heart
into
sth.全神贯注于某事
(2)(使)调节焦距
③Let
your
eyes
focus
on
objects
that
are
further
away
from
you.
睁大眼睛看清楚离你较远的物体。
④The
television
cameras
are
focused
on
the
crowd.
电视摄像机的镜头聚焦于人群。
[归纳拓展]
focus
n．[U，C]焦点；中心点
the
focus
of
attention关注的焦点
bring
into
focus使集中在焦点上，使清楚起来
⑤It
was
the
main
focus
of
attention
at
the
meeting.
这是会议上关注的主要焦点。
[即境活用]
完成句子
①When
studying，he________
________
________
________(集中注意力于)his
lessons.
②Bring
the
object________
________(在焦点上)if
you
want
a
good
photo.
答案：①focused
his
attention
on　②into
focus
4.
reduce
vt.减少；减缩
①It
was
foggy
so
the
driver
had
to
reduce
speed
to
forty
kilometres
an
hour.
由于大雾，司机不得不把速度减到每小时40千米。
②If
you
buy
more
than
ten，they
will
reduce
the
price
by
10
percent.
你如果买10个以上他们就会把价格降低百分之十。
③The
number
of
the
cars
was
reduced
from
40
to
30.
汽车数量由40辆减少到30辆。
④The
number
of
the
cars
was
reduced
by
10%.
汽车数量减少了10%。
⑤The
population
has
increased
by
15
percent.
人口增长了15%。
[即境活用]
用适当的介词填空
①Production
costs
have
been
reduced________30%.
②The
population
has
increased
from
1.2
million________1.8
million
in
this
city
this
year.
答案：①by　②to
5.
keep...free
from
/of使……免受(影响或伤害等)；使……不含(有害物
①Parents
should
keep
their
children
free
from
harm.
家长不应该让孩子受到伤害。
②Lydia
has
been
completely
free
from
cancer
since
1995.
自从1995年以来莉迪娅就已经完全地治愈了癌症。
③They
like
living
in
a
village，free
from/of
crowds
and
noises.
他们喜欢住在村子里，远离人群和喧闹。
④She
got
the
ticket
free
of
charge.
她免费得到了这张票。
⑤These
exercises
help
free
the
body
of
tension.
这些锻炼可以使紧张的身体放松。
[归纳拓展]
be
free
from
/
of无……的
be
free
to
do
sth.自由地做……
free
sb./sth.of
/from
sth.
使某人/
某物摆脱/
除去……
[即境活用]
完成句子
①使这个地方除了学习资料外没有任何东西。
________this
space________
________everything
but
study
materials.
②用了很长时间才把遇险者从倒塌的建筑物中解救出来。
It
took
hours
to________the
victims________the
collapsed
building.
答案：①Keep；free
of　②free；from
comment
(1)n.评论；议论
①She
was
asked
about
the
pay
increase
but
made
no
comment.
询问她加薪问题但是她不进行评论。
②He
made
no
comment
on
our
proposal.
他对我们的建议没有作评论。
③—Will
you
resign，Minister?
——部长，你要辞职吗？
—No
comment!
——无可奉告！
[归纳拓展]
make
comments
on
/upon
/about
sth.评论某事
without
comment不必多说
no
comment无可奉告
(2)vt.&
vi.表达意见；作出评论
④He
commented
that
she
was
not
fit
for
the
job.
他评论说她不称职。
⑤Can
you
comment
on
the
conclusion?
你能对这一结论发表意见吗？
[归纳拓展]
comment
on...对……发表评论
comment
that...评论说……
[即境活用]
完成句子
①您对这起事故发生的原因有何评论？
Have
you
any
________
________
________
________
the
cause
of
the
accident?
②发言人拒绝对这件事发表评论。
The
spokesman
refused
to
________
________
the
matter.
③她评论说这是一部很精彩的电影。
She________
________it
was
an
excellent
film.
答案：①comment
to
make
about　②comment
on
③commented
that
句式剖析
1.
①Experience
will
make
him
a
man.
经验会使他成为一个堂堂的男子汉。
②The
smell
of
cooking
makes
me
hungry.
烧菜的味道令我感到肚子饿。
③She
made
her
children
wash
their
hands
before
eating.
她要孩子们在吃东西前洗手。
④When
I
first
came
to
New
York，I
had
a
lot
of
trouble
making
myself
understood.
我刚到纽约时，想让人听懂我的话非常困难。
[即境活用]
完成句子
①The
noise
in
the
school________
________
________(让人很难安心学习)．
②The
teacher
tried
his
best
to________
________
________
________
________
________
________
________(使自己成为他的学生的好朋友)．
答案：①makes
learning
difficult　②make
himself
a
good
friend
of
his
students
2.
They
often
change
the
kind
of
crop
in
each
field
every
few
years，for
example，growing
corn
or
wheat
and
then
the
next
year
peas
or
soybeans.在同一块地里，他们经常每隔几年就换种农作物。例如，种玉米或小麦后，来年再改种豌豆或大豆。(P14)
every与数词或few，other连用，表示时间或空间的间隔，其结构如下：
①every
four
years＝every
fourth
year每四年
②every
ten
metres＝every
tenth
metre每十米
③every
two
lines＝every
other/second
line
每两行/每隔一行
④They
planted
a
tree
every
few
metres
along
the
road.
他们沿着路每隔几米种一棵树。
⑤Do
you
go
home
every
two
months/other
month/second
month?
你每隔一月回家一次吗？
[即境活用]
完成句子
①我们每走几英里就得停一停。
We
had
to
stop________
________
________.
②他们隔周来看我一次。
They
visit
us________
________
________.
答案：①every
few
miles　②every
other
week
Bye-bye