粘住-指挥刀
Topic 3
Reading
In
the
United
States,
employees
typically
work
five
days
a
week
for
eight
hours
each
day.
However,
many employees want to work a four-day
week and are willing to accept less pay
in
order to do so. A
mandatory policy requiring companies to
offer their employees the option
of
working a four-day
workweek for four-fifths (80 percent) of their
normal pay would benefit the
economy as
a whole as well as the individual companies and
the employees who decided to take
the
option.
The
shortened
workweek
would
increase
company
profits
because
employees
would
feel
more
rested and alert, and as a result, they
would make fewer costly errors in their work.
Hiring more
staff
to
ensure
that
the
same
amount
of
work
would
be
accomplished
would
not
result
in
additional payroll costs because four-
day employees would only be paid 80 percent of the
normal
rate.
In
the
end,
companies
would
have
fewer
overworked
and
error-prone
employees
for
the
same
money, which would increase company benefits.
For the country
as a whole, one of the primary benefits of
offering this option to employees is that
it would reduce unemployment rate. If
many full-time employees started working fewer
hours,
some of their workload would
have to be shifted to others. Thus, for every four
employees who
went on an 80 percent
week, a new employee could be hired at the 80
percent rate.
Finally, the option of a four-day
workweek would be better for individual employees.
Employees
who could afford a lower
salary in exchange for more free time could
improve the quality of their
lives by
spending the extra time with their families,
pursuing private interests or enjoying leisure
activities.
Topic 3
Listening
Offering employees
the options of four-
day work week won’t
affect company profits, econo
mic
conditions or the lives of employees in
the ways the reading suggests?
First, offering a four-day
work week will probably force companies to spend
more, possibly a lot
more.
Adding
more
workers
means
putting
much
more
money
into
providing
training
and
medical
benefits.
Remember,
the
costs
of
things
like
health
benefits
can
be
the
same
whether
employees works four days or five. And
having more employees also requires more office
space
and more computers. These
additional costs will quickly cut into company
profits.
Second, with respect to overall
employment, it doesn’t follow that when some
employees choose a
four-day work week,
many more jobs will become available. Hiring a new
worker is costly, as I
argued
a
moment
ago;
and
companies
have
other
options:
they
might
just
choose
to
ask
their
employees
to
work
overtime
to
make
up
the
difference.
Worst,
companies
might
raise
their
expectations;
they
might
start
to
expect
their
four-day
employees
can
do
the
same
amount
of
work they used to do in five days. If
this happens, then no additional jobs will be
created, and
current jobs will become
more unpleasant.
Finally, while a four-day work week
offers employees more free time to invest on their
personal
lives, it also presents some
risks that could end up reducing their quality of
their live. Working a
shorter week can
decrease employees’ job stabilities and harm their
chances for advancing their
careers.
Four-day
employees
are
likely
to
be
the
first
to
lose
their
jobs
during
an
economic
downturn. They may
also be passed over for promotions because
companies might prefer to have
five-day
employees
in
the
management
positions
to
ensure
continuous
coverage
and
consistent
supervision for the entire work week.
Topic 3
Answer
The reading and listening passages have
a conflict of opinion about the proposal of a
four-day
workweek for eighty percent of
salary. The reading passage points out its three
benefits, which
are contradicted by the
following lecture.
First,
the reading passage believes
that the
plan will
increase company’s profits
because hiring
more employees will not
increase company’s costs. However, the speaker
believes that this is not
the
case.
For
one
thing,
more
employees
mean
more
training
costs
and
medical
benefits.
For
another thing, companies will have to
spend more on office spaces and computers.
Second,
the
reading
passage
argues
that
the
plan
will
reduce
unemployment
rate
because
if
employees work fewer hours, companies
will have to employ more people. Yet, the speaker
holds
the
opposite
opinion.
He
argues
that
companies
will
ask
employees
to
work
overtime
or
raise
work expectations
instead of hiring more.
Finally,
the
reading
passage
points
out
the
plan will
improve
the
quality
of
lives
of
employees.
However, the
speaker believes that this is not the case because
employees will be more likely to
lose
their jobs and less likely to be promoted to
higher positions.
Topic 4
Reading
Soon there will be something new for
the tourist who has been everywhere and seen
everything
on Earth. Spacecraft being
developed by private commercial companies will
soon enable private
citizens to buy
their own tickets to travel into space, thereby
creating a space tourism industry.
So
far, space travel has been undertaken only by
governments, but the new, privatized spaceflight
industry will bring great benefits to
both science and the public.
First, private space travel will
benefit serious space exploration by making
spaceflight cheaper.
Privatization
of
space
technology
will
bring
technological
costs
down
very
fast
because
it
will
allow
competition
—
and
competition
is
one
of
the
strongest
motivators
to
cut
costs.
Thus,
lowering the cost of
space travel will benefit not only space tourists
but also scientists, who will be
able
to use private space flights for research
purposes.
Furthermore,
privatization of space travel will accelerate the
rate at which important scientific
discoveries occur. The aerospace
industry already
sponsors
发起，主办
a
lot of groundbreaking
scientific
research,
and
adding
private
spaceflight
companies
to
it
will
make
the
industry
as
a
whole grow
in size, thereby employing more scientists than it
does now. That increased number of
working scientists means not only that
more discoveries are likely to be made but also
that those
discoveries are likely to be
made more quickly than in the past.
Finally, when governments are the sole
providers
of space travel,
the costs are paid for by the
whole taxpaying public, but with
privatization, the expenses of space travel will
be borne by the
customers of the
industry. The fact that private spaceflight
operators will be able to raise funds
through ticket sales means that the
financial burden on taxpayers will be eased
significantly.
Topic 4
Listening
Well, it looks as though we’ll soon see
private spacesh
ips carrying tourists
into space. But will it
really provide
great benefits for serious science and for the
public? I don’t think so.
First, privatized space travel, which
is extraordinarily expensive, is likely to stay
that way. For
one
thing,
commercial
space
travel
will
require
an
elaborate
space
traffic-control
system
to
prevent
collisions
—and the development and
operation of such a system won’t come cheap
either.
Another
thing
that’ll
keep
costs
high
is
tested
and
retested—
and
that
also
tends
to
be
a
very
expensive process. Both of those costs
will be reflected in the prices of the spaceflight
tickets, so
no one should expect the
cost of space flights to go down fast.
Second,
if
commercial
spaceflight
has
any
effect
at
all
on
the
rate
of
scientific
discovery
and
innovation, it will be
to delay or even prevent such discovery and
innovation. If the best and the
brightest engineers get lured away from
government space programs by the high salaries
offered
by
private,
for-profit
companies,
they
might
end
up
working
on
commercial
stuff
that
doesn't
have
much scientific value. And as a result, serious
space research might actually suffer.
And finally, will
the
taxpaying public get off the hook financially? No
chance! The fact is
that
so-
called
private
space
tourism
isn’t
possible
without
huge
public
tax
subsidies.
It
will
take
billions
and
billions
of
dollars
to
build
space
stations,
space
airports,
and
so
on,
and
private
investors
simply
cannot
raise
such
huge
amounts.
So
the
burden
on
taxpayers
won’t
be
significantly
eased
with
the
development
of
the
private
spaceflight
industry.
In
fact,
all
taxpayers’ll be paying more to
subsidize the vacations of the space
tourists.
Topic 5
Reading
Donating part of one’s income to public
causes, known as charitable givin
g,
used to be a common
practice.
But,
in
the
United
States
charitable
giving
has
declined
substantially
in
recent
years,
and, for several reasons, it is
unlikely to increase in the future.
One reason that charitable giving has
fallen is simply that there is less need for
charitable giving,
because the United
States government now provides most of the
important public services. The
government assumes
承担
much of the
responsibility for feeding the poor, providing
health care,
and
taking
care
of
the
victims
of
natural
disasters
—
functions
that
charities
used
to
perform.
These government
institutions of social welfare are permanent, and
so the diminished need for
private
charitable giving will also be permanent.
Another reason people are,
and will be, giving less to charities is that in
the past few years there
have been
highly publicized disclosures that the managers of
some prominent national charities
were
receiving huge salaries and other benefits as
large or larger than salaries of heads of major
for-profit
corporations.
These
salaries
and
expenses
for
travel,
fancy
offices,
and
advertising
significantly
reduce the percentage of donated money that went
to charitable purposes. Naturally
people have been turned off
厌烦
by these excesses and
inefficiencies.
Finally,
beyond the shortcomings of legitimate charities,
there has been an increasing number of
fraudulent
solicitations
恳求，劝诱
by organizations or individuals who
merely pose as charities.
As a result,
people are now becoming skeptical even about what
are in fact legitimate appeals for
support.
So
potential
donors
are
starting
to
give
less
and
give
less
frequently.
And
since
the
incidence of charity fraud seems to be
increasing, we can expect further declines N. in
charitable
giving as people become more
concerned that they are being taken advantage of.
Topic 5
Listening
There’s no doubt that giving to
charities has declined in recent years, but there
are
good reasons
to think
it’ll soon begin to go up.
Consider, for example, the fact that
the number of elderly and retired people in our
society keeps
growing.
Right
now,
elderly
citizens
who
can’t
afford
health
care
often
rely
on
government
programs
to
pay
for
it.
But
as
the
elderly
population
grows,
government
programs
probably
won’t be able to
cover the health assistance, Americans respond to
that need. And since the need
will be
increasing, we should expect to see charitable
giving rise accordingly.
The
re’s another reason to be
optimistic about the future of charitable giving.
The disclosures of
waste and bad
management at major charities, and people’s anger
at this waste, are producing
significant
reforms.
Overpaid
managers
have
been
forced
to
resign
by
the
bad
publicity.
Charities are
reducing their expenses and are now
subject to
服从
closer public scrutiny.
As a
result, people are regaining confidence
that the money they donate will support the causes
they
care about.
People’s reaction to charity fraud is
also evolving
正在发展
. In the
short run, people don’t want
to donate
because they
’re concerned with whether
charities are honest. But in the long run, such
skepticism makes people careful, not
stingy. For example, many people now refuse to
give money
when they’re asked to do so
over the telephone. They insist on receiving proof
and doc
umentation
before
they donate. Just as people learn how to be
careful consumers, most people are acquiring
the skills needed to guard against
charity fraud without stopping their support for
worthwhile
causes.
Topic 6
Reading
It used to be that parents took their
children on vacation during the summer, when
school was
out of session. But today,
much more often than in the past, many parents
take their children on
vacation
during
the
school
year.
Although
these
children
are
away
from
school,
sometimes
for
several weeks, traveling
itself serves a valuable educational function.
The most important
educational benefit of taking children on vacation
is that traveling exposes
children to
new places and cultures. It is good for children
to read about distant countries, but it
is even better to take them there. What
students learn by meeting the people and absorbing
the
culture of these places is
something they could not learn in their
classrooms.
Moreover, the
benefits to the children who have been away from
the classroom for several weeks
traveling continue after they have
returned to their classes. Students who are in
school every day
of the school year can
easily lose enthusiasm for their studies. But
students invigorated by time
away
return with heightened excitement.
The
trend
of
students
taking
vacations
during
the
school
year
also
has
benefits
for
teachers.
When these students return to school,
their knowledge and enthusiasm
contribute positively to
the entire
class. Teachers can ask the children to share
stories of their travels with their peers and
can incorporate what they have learned
from traveling into writing and reading projects.
This
makes lesson development easier
for teachers because the returning students’
experiences provide
a ready basis for
classroom discussions and projects.
Topic 6 Listening
Now,
let’s
consider
how
taking
children
on
vacation
when
school
is
in
session
impacts
their
education. I believe
the impact on children and their teachers can be
quite negative.
While
students have been traveling, their fellow
students have been working. What do you think
happens when they return to school?
Well, they have to spend a lot of time “playing
catch
-
up,”
you
know, doing work that fellow students have already
done. It’s one thing to miss a day or
two
of
school,
but
many
parents
take
their
children
on
vacation
for
weeks
on
end,
and
it’s
very
difficult
for
any
child
to
make
up
that
much
missed
time.
So,
the
missed
learning
has
to
be
weighed against the
benefits of traveling and learning about other
cultures. On balance, what is
lost is
greater than what is gained.
When children come back to class after
a long trip, they’re excited about their recent
adventures.
Sounds good, but this
enthusiasm can have a downside. Their excitement
can make it difficult for
them to fit
back into the routine of the school day. School
seems a little boring to them, so they’re
not attentive to their studies, and
their restlessness can distract other students.
When a student is
distracted or has to catch up on missed
wor
k, there’s a negative effect on the
teacher
too.
Teachers
have
lesson
plans
that
detail,
day
by
day,
what
they
are
going
to
teach.
When a student is
absent from the classroom, this interferes with a
teacher’s plan for that student.
And
if
teachers
spend
time
helping
a
few
students
catch
up,
they
have
less
time
for
other
students… so they suffer
too.
Topic 7
Reading
Easter Island, a small, remote island
in the Pacific Ocean, was once home to a
flourishing culture.
But about 500
years ago (A. D. 1500), its society went into a
steep decline. History teaches us that
events
like
this
are
often
caused
by
outside
influences.
So
it
is
not
unreasonable
to
consider
whether there are
facts about the decline of Easter Island’s society
that would be explained by a
hypothesis
of an invasion.
One
such
fact
has
to
do
with
trees.
Most
Pacific
island
societies
have
managed
to
find
an
ecologically balanced way
of living by using
—
but not
overexploiting
—
natural
resources such as
trees. Most Pacific
islands, therefore, remain
lush
—
but not Easter Island.
Although it was once
densely
forested,
most
of
its
trees
had
disappeared
by
about
500
years
ago.
Environmental
destruction of this sort has often been
caused by invaders who deplete an area’s natural
resources
without any concern for the
future.
Facts about the
large stone statues on Easter Island could also
support the idea of an invasion.
There
are about 900 of these statues on the island; the
largest is over 20 meters tall. The native
society clearly
placed a
great deal
of importance on their
production.
Yet about the same
time
that
the
island
became
deforested,
islanders
stopped
making
these
huge
statues.
An
invasion
would help explain
why this traditional practice came to a sudden
end.
Furthermore,
we
know
that
around
the
time
these
other
changes
were
taking
place,
a
new
religion
developed
on
Easter
Island:
the
“Birdman”
worship.
There
is
no
convincing
evidence
that the Birdman
religion existed before 1500, which suggests that
this new religious practice may
have
been introduced by outsiders.
Topic 7
Listening
The idea considered in the
reading is not unreasonable in the abstract, but
all the concrete
evidence points to
internal causes for the decline of Easter Island’s
culture 500 years ago. It’s a
sad story
of a native culture that did not have the
foresight to sustain itself.
In the centuries before 1500, the
inhabitants of Easter Island were prosperous… so
prosperous
that
they
were
able
to
invest
extra
time
and
energy
in
building
giant
statues,
which
became
important signs of
status. Different island communities began
competing as to who could erect
the
most statues. Now here’s where the problem for
trees comes in: archaeological evidence shows
that the islanders used tree logs to
move the statues into position. So, as the number
of statues
increased, more and more
trees had to be cut, until finally, 500 years ago,
there were no more left.
Of
course, once the trees were gone, the islander
could no longer build rafts to fish at sea, and so
they could no longer catch big fish. As
the necessities of life became harder and harder
to get, the
islanders no longer had the
time and energy to create big statues. Without
logs, of course, they
couldn't move the
statues anyway, so naturally the interest in
making the statues declined.
Finally, it would not be surprising if
the islanders lost confidence in their old gods
when life on
the island became a
struggle for survival. I
mean, the old
gods wouldn’t seem to be protecting
them any more. So it would be natural
for the islanders to have developed a different
religious
idea, hoping that the new god
would ensure them a better life.
Topic 8
Reading
When a company needs to hire someone
for a managerial position, there is often a choice
between
promoting an employee who is
already working inside the company or bringing in
a person from
outside. Hiring a
qualified outsider is often to a company’s
advantage for several reasons.
An important reason for
hiring outsiders as managers is that they bring a
new perspective. This
contributes to
the diversity of ideas and allows company
practices to be seen in a new light. Often,
an outside hire will ask, “What’s the
reason for doing things this way?” This question
may lead to
a reevaluation of practices
that are actually
inefficient but have
become
so
much a part of the
routine that it’s difficult for
insiders to question them.
Another major factor to be considered
is the cost of on-the-job training. Hiring
outsiders allows a
company to look for
people who already have the particular skills and
experience required for
the job. The
company will not have to spend time and money
training an internal employee for
the
new job
—
something that has
to be done when, for example, an employee is
promoted from a
technical
position
to
a
managerial
one.
In
such
a
case,
usually
the
employee
would
be
sent
to
classes
to help learn needed managerial skills.
Finally,
managers
hired
from
the
outside
will
often
have
business
contacts
with
suppliers,
customers, and technicians that they
have developed in their previous job. Clearly
these contacts
can be a valuable asset
for the company that hires managers from the
outside.
Topic
8
Listening
For
some
of
the
reasons
presented
in
the
reading,
many
companies
have
a
policy
of
hiring
outsiders to fill managerial positions.
However, a closer examination will show that the
policy is
misguided.
First of all, the new perspective an
outsider brings into the company’s corporate
structure often
leads to conflict in
the managerial team. Companies often have specific
corporate philosoph
ies…
(for
example, about how decisions are to be reached and
how work is to be organized). So when
outsiders
bring
with
them
a
significantly
different
philosophy,
this
can
create
serious
disagreement and
conflict… and make it difficult for the managerial
t
eam as a whole to function
smoothly
and
efficiently.
An
internal
employee,
by
contrast,
is
more
likely
to
know
company
tradition.
Another
point
to
note
is
that
hiring
outsiders
may
entail
an
additional
cost
that
perhaps
isn’t
obvious.
It’s
true
that
outsi
de
hires
may
come
with
required
managerial
skills
and
experience.
But
to
become
effective
as
managers
in
a
new
company,
they
also
have
to
establish
personal
relationships
with
their
new
colleagues
—
get
to
know
them
and
win
their
trust.
This
can
often
take more time than
one would expect, and an uncomfortable settling-in
period between a new
boss
and
workers
can
also
be
more
costly
in
lost
productivity
than
on-the-job
training
for
an
internal
employee.
Finally, suppose
a company makes a point of hiring outsiders as
managers instead of promoting
insiders.
Well, that company will soon find that its own
best employees will have not choice but to
look
to
advance
their
own
careers
outside
the
company.
And
when
these
key
employees
leave,
they will also take their valuable
business contacts away with them to their new
employer.
Topic 9
Reading
Scant physical
evidence remains of the first human domestication
of grain. Still, there is enough
to
conclude that ancient peoples, motivated by the
nutritional value of bread or cakes made of
wild
wheat,
looked
for
controlled
ways
to
grow
it
to
provide
a
consistent
food
supply.
Three
related discoveries are likely to have
led to the introduction of bread as the first
grain-based food.
The first
discovery was that wheat could be prepared for use
by grinding. People probably began
consuming wheat by chewing it raw.
Because wheat is very hard, they gradually
discovered that
it was less trouble to
eat if crushed to paste between two
stones
—
the result would have
been the
ancestor of the drier, more
powdery wheat flour we use today.
From
there,
it
was
a
short
step
to
the
next
breakthrough:
baking
the
simplest
bread,
which
requires no technology
but fire. Loaves of wheat paste, when baked into
bread, could be stored
for long
periods, certainly longer than raw seeds. This
kept the food value of wheat available for
an extended period after it had been
harvested.
Finally, ancient
peoples found that, if the paste was allowed to
sit in the open, yeast spores from
the
air settled on it and began fermenting the wheat.
This natural process of fermentation caused
bubbles to from in the wheat paste that
suggested it would be lighter in texture and even
easier to
eat when baked.
Topic 9
Listening
Conventional
wisdom
says
that
a
very
primitive
kind
of
bread
was
the
first
grain
food
that
human
societies
ate.
But,
you
know,
for
the
last
few
decades,
there’s
been
an
alternative
hypothesis that
quite a few anthropologists are starting to give a
closer look. That hypotheses says
that
is was, in fact, beer
—
not
bread
—
that was the first
again food. Sound strange? Consider a
couple of things.
For one thing, you don’t have to grind
wheat to make it easier to eat. If you keep it in
a moist
environment, it naturally
starts sprouting, with a new baby plant splitting
the hard seed case in
half.
Sprouted
wheat
is
sweeter,
softer,
and
actually
more
nutritious
than
whole
wheat
seeds
—
and
it
would
have
developed
without
human
bright
idea
of
crushing
it.
In
order
to
discover
the
usefulness
of
ground
wheat,
someone
gad
to
get
the
bright
idea
of
crushing
it.
To
discover the
usefulness of sprouted wheat, people just had to
do nothing and let it sit. Which do
you
think happened first?
Another thing: what turns grain into
beer is fermentation, and wheat begins to ferment
almost as
soon
as
it’s
stored—
from
water
and
yeasts
in
the
air.
After
the
wheat
sprouted,
it
would
have
started to ferment. The process would
have been obvious because of the bubbles and foam
that
formed. People could have
experimented by tasting it and discovering the
first beer.
And even if you
assume that people were already grinding wheat to
paste, think about it. The
paste
ferments
and bubbles.
Is
it
likely
that
early
peoples
would
have
thought
to
fire
it
before
eating? We’re used to cooking our
food,
but in prehistoric times, the
idea that you would take fire
to food
to improve it for eating was not obvious.
Topic 10
Reading
Wilderness management has advanced
greatly over the last century, due in part to such
practices
as the suppression of forest
fired and limitations on the clear-cutting of
trees. Monitoring forests
for
small
brushfires
is
easier
with
aircraft,
as
is
the
use
of
large
amounts
of
water
and
sophisticated chemical fire
extinguishers to prevent fires from spreading.
The
goals
decreasing
the
amount
of
destruction
by
fires
and
cutting
are
wide-ranging.
One
is
simply the
longer lives and improved health of trees. In some
areas of hickory and oak forest on
the
Eastern
Seaboard,
fire
suppression
has
allowed
the
maturation
of
so
many
trees
that
the
treetops form a
continuous canopy.
There is
evidence of the healthful effects of fire
suppression closer to the ground as well. Vines
and low bushes that would be burned out
in a forest fire can flourish when fires are
suppressed,
of course, but there is a
more indirect way fires harm plant life. Chemical
tests on areas that have
recently
experienced
forest
fires
demonstrate
that
burning
decreases
the
overall
amount
of
nutrients
in
the
soil.
Suppressing
fires
prevents
such
a
decrease.
Ferns,
wildflowers
and
herbs
grow
without disturbance.
Finally, wildlife can benefit. In the
eastern hickory and oak forest, the suppression of
fires has
meant that forest animals---
ranging from small insects and birds
to
large deer and bears
—
are
not burned to death. Deer populations,
in particular, have increased notably.
Topic 10
Listening
For years, forest fires were regarded
as uniformly destructive, and forest managers put
a lot of
effort into preventing them.
But it turns out that fire suppression may have
destructive long-term
effects on the
forests it’s supposed to protect.
For instance, mature oaks
have grown so thickly in some places that little
light reaches the forest
floor. But
young oak trees need light in order to grow
properly. The lack of light has meant that
new oaks aren’t maturing rapidly enough
to replace the older oaks. It also means that
other tree
species that don’t need so
much light, such as maples, are invading oak and
hickory forests and
competing for
resource.
There are
competition problems at ground level too. What
forest fires, both natural and artificial,
used
to
do
is
burn
off
some
of
the
plants
on
the
forest
floor
before
they
could
grow
into
huge
thickets. Now they
run wild
over the ground
—and again, that means
it’s hard for young
trees
and other native plants to grow.
Then
there’s
the
increase
in
the
deer
population—
this
partially
results
from
the
lack
of
forest
fires
and partially from limitations on
hunting
—
but the thing is,
deer like to eat the leaves off oak
saplings. So if one of those oak
seedlings somehow does manage to get a good start,
despite the
shade and all the other
plants competing for nutrients, it’s likely to be
killed by having its leaves
eaten.
Oh, and one other thing:
Scientists are now finding that forest fires
release nutrients from
the
plants and animals that are burned.
That means that, even though the total amount of
nutrients
is decreased, there can
actually be more nutrients available on the soil
surface for plants that are
trying to
grow back afterward.
Topic
11
Reading
Around 1130 A.D., a group of highly
intelligent and creative humans called the Anasazi
from New
Mexico’s
Chaco
Canyon
vanished without
a
trace.
Judging
from
available
evidence,
historians
have
suggested
that
the
Anasazi’s
disappearance
was
mor
e
likely
to
be
caused
by
a
severe
summer drought.
First of all, the time when
the Anasazi abandoned their villages coincided
with the beginning of a
sixty-year
summer drought caused by global warming. During
this time, uncommonly long heat
waves
swept across the world, making colder regions
warmer and causing severe drought in the
Americas. Scientists believe that the
summer
drought at Chaco Canyon was
so severe
that the
Anasazi
could not cope with
it. In the end, they were forced
to choose between starvation
and
migration.
Second, at Chaco Canyon, archeologists
have discovered irrigation systems including
diversion
dams and canals
directing water to the fields.
The presence of these
systems
indicates that
the
Anasazi suffered
shortages of water, and as a countermeasure for
the crisis, they built irrigation
systems
to
store
water
for
drinking
and
growing
crops.
However,
the
drought
caused
by
the
global
warming
eventually
may
have
been
so
overwhelming
that
it
compelled
the
Anasazi
to
leave.
Finally,
before
the
big
summer
drought,
Chaco
Canyon’s
natural
springs
and
fertile
soil
contributed to the tribe’s population
growth. Perhaps, the tribe’s population had
overgrown, and
then
the
people
were
approaching
the
limit
of
local
resources
during
the
sixty-year
summer
drought. The
subsequent food shortages forced this ancient
people to migrate to a more habitable
area.
The
fact
that
the
Anasazi
abruptly
fled
from
their
dwelling
and
left
behind
numerous
artifacts suggests that they were
displaced by a major natural disaster.
Topic 11
Listening
I
think the evidence supporting the claim that the
Anasazi disappeared because of severe drought
is shaky.
First
of
all,
there
may
have
been
a
global
warming
in
the
past,
and
the
subsequent
droughts
throughout the world affected different
places, but the global warming did not affect
areas where
the
Anasazi
lived.
The
evidence
suggests
that
some
trees
have
existed
at
Chaco
Canyon
for
thousands of years. If there had been a
drought at Chaco Canyon, these trees would
probably
have died.
Second, the fact that irrigation
systems such as dams and canals were found in
planes where the
Anasazi lived does not
necessarily mean that this prehistoric tribe
suffered severe droughts and
abandoned
their homeland as a result. On the contrary, the
irrigation systems that existed for 150
years would indicate that the Anasazi
were fully aware of their problems of water
shortages and
they somehow developed
the technology to store water and divert it to
grow corn, squash, and
beans
in
a
desert-like
land.
Scientists
have
found
evidence
that
the
Anasazi
providently
stored
their crops against
drought years, suggesting that this prehistoric
people did not vanish because
of a
drought.
Finally,
drought
is
only
a
hypothesis
for
the
Anasazi’s
disappeara
nce.
Recent
findings
by
climatologists suggest
that the great drought at Chaco Canyon was not
severe enough to drive a
nation
of
people
to
abandon
their
homes.
The
fact
that
the
Anasazi
abruptly
left
their
homes
might
suggest they were attacked by another warring
tribe rather than threatened by a drought.
We
should
also
consider
other
causes
such
as
disease
or
overuse
of
farmland.
In
sum,
the
evidence so far is not
enough to support the claim that the Anasazi
vanished simply because of a
severe
drought.