时间:2018-12-15 作者:英语课 分类:VOA慢速英语2008年(八)月


英语课

This is the VOA Special English Development Report.


Clay is found almost everywhere in the world. It is formed by the action of wind and water on rocks over thousands of years. The rocks change in both chemical and physical ways. Chemically, elements like potassium and aluminum 1 are added and taken away. Physically 2, the rocks break down into smaller and smaller pieces. After a long time, some of the rock changes to clay.


Clay is important because it is used around the world to make containers of all kinds. Potters add water to soften 3 the clay. This makes it easier to form into shapes by hand or by machine. Then it is fired in an extremely hot stove. The result is a container with a hard surface that will last for many years.


In many countries, clay was formed from volcanoes 4. This kind of clay usually contains many minerals. So the fires to make containers from volcanic 5 clay must be hotter than those used for non-volcanic clay. The fires may be as hot as one thousand four hundred degrees Celsius 6.


It is also important to dry the clay containers slowly. This means that the highest temperature should not be reached too fast.


You can add materials to clay to gain desired results. For example, you can add sand to prevent tiny breaks or lines from forming in the finished product. But you should not use sand from the coasts of oceans. Instead, you should use sand from rivers or from other areas of land that are not near the sea.


You can usually find good clay in low areas of islands or land, especially if volcanoes helped form the land. Clay often exists in fields covered with some water. The clay will be found about one meter below the ground. River banks often also have clay about one meter or less under the surface.


You can recognize clay because it is very shiny when it is wet. You can also perform a test. Take some of the material and add enough water to it to make it seem like you are making bread. Then press it in your hand until it is about the size of an egg. It is probably clay if it holds together instead of falling apart when you stop pressing.


And that's the VOA Special English Development Report, written by Gary Garriott. Guides to working with clay and other materials can be found on the EnterpriseWorks/VITA list of publications 7. These publications can be ordered for a charge. The list is at enterpriseworks.org. Transcripts 8 and MP3 archives of our reports are at voaspecialenglish.com.



1 aluminum
n.(aluminium)铝
  • The aluminum sheets cannot be too much thicker than 0.04 inches.铝板厚度不能超过0.04英寸。
  • During the launch phase,it would ride in a protective aluminum shell.在发射阶段,它盛在一只保护的铝壳里。
2 physically
adj.物质上,体格上,身体上,按自然规律
  • He was out of sorts physically,as well as disordered mentally.他浑身不舒服,心绪也很乱。
  • Every time I think about it I feel physically sick.一想起那件事我就感到极恶心。
3 soften
v.(使)变柔软;(使)变柔和
  • Plastics will soften when exposed to heat.塑料适当加热就可以软化。
  • This special cream will help to soften up our skin.这种特殊的护肤霜有助于使皮肤变得柔软。
4 volcanoes
n.火山( volcano的名词复数 )
  • Volcanoes and geysers erupt. 火山和间歇喷泉均能喷发。 来自《简明英汉词典》
  • He has been able to tell us more about active volcanoes than any man alive. 他现在比任何人都能更多地向我们讲述有关活火山的情况。 来自《用法词典》
5 volcanic
adj.火山的;象火山的;由火山引起的
  • There have been several volcanic eruptions this year.今年火山爆发了好几次。
  • Volcanic activity has created thermal springs and boiling mud pools.火山活动产生了温泉和沸腾的泥浆池。
6 Celsius
adj.摄氏温度计的,摄氏的
  • The temperature tonight will fall to seven degrees Celsius.今晚气温将下降到七摄氏度。
  • The maximum temperature in July may be 36 degrees Celsius.七月份最高温度可能达到36摄氏度。
7 publications
n.发表( publication的名词复数 );公布;出版;出版物
  • The related publications are far too numerous to list individually. 相关出版物太多,没法一一列举。 来自《简明英汉词典》
  • A detailed list of our publications is available on request. 我们的出版物有一份详细的目录备索。 来自《简明英汉词典》
8 transcripts
n.抄本( transcript的名词复数 );转写本;文字本;副本
  • Like mRNA, both tRNA and rRNA are transcripts of chromosomal DNA. tRNA及rRNA同mRNA一样,都是染色体DNA的转录产物。 来自辞典例句
  • You can't take the transfer students'exam without your transcripts. 没有成绩证明书,你就不能参加转学考试。 来自辞典例句
学英语单词
-xion
advanced intelligent tape
aft side light
anguilla australis
antioxidase
approach control office
attainor
aurian
available current surplus
back-off compensation
blow-molded container
bottle glorifier
brooksie
carved wooden jewellery box
clonal selection
Crack a nut with a sledgehammer
crawl up
cryosphere
Cumbres de Monterrey National Park
curved mould
de(s)aminase
discrete wired circuits
doand
Eocretaceous
fair point
fencepole
fenice
foeniculum vulgares
fourth-rail insulator
fucus
fuel-charging chamber
gaol
geminal diols
great circle path
hard pine
have a notion that...
hot brittleness test
hydraulically actuated brake
hyper-pre-beta-lipoproteinemia
independent tank
insectator
internal inner ring
Iwo Jima
Japanese medlar
jugendherbergens
kahikatoa
KCMG, K.C.M.G.
lexicostatisticss
lip-reads
loop splice plate
manetta
metal bead
Metriophyllum
molecular momentum exchange
multiprocess special character
myelochroa denegans
Natronkatapleite
naut mi
neutral skin
nonlinear stochastic function
nonwood
Orisha
Osvaldo Cruz
overhead distribution
overthrusts
oxyphonia
parallel diode limiter
Pas.
pecan pies
perforated (paper)tape
Plaimpied-Givaudins
posthumous adoption
pple
rabid
ratherish
reapplied
reception expenses
rubber stop
safe curve speed
saw-grass
seagoing buoy tender
show a fair pair of heels
solid state keyboard
spicy food
stange
stem tube
stufs
superconductive chopper
supply grill
toryhillite
Tschermak
tubular pump-turbine
tumbledryers
tutorial disk
twist the knife
underbackorder
unlight
vent-type injection moulding
weak-to-the-wall
wielders
wooden shoes
Yokjido