时间:2018-12-30 作者:英语课 分类:托福听力短文


英语课
(MA) Look at our topographical map and you'll see that the middle third of the North American continent --- from the Rocky Mountains almost to the Mississippi River --- is pretty flat. This is the Great Plains. This kind of area is sometimes called a prairie, sometimes a steppe. That's [ess-tee-ee-pee-pee- ee]. The defining features are level terrain 1, dry climate, and an absence of trees. The Great Plains are actually the former bed of shallow inland sea. Over millions of years, sediment 2 left by glaciers 3, water, and wind smoothed out the dry sea bed.

As I said, the Great Plaints are bordered on the west by the Rocky Mountains. And it's really the Rockies that are responsible for the formation of the grasslands 4. The mountains are so high that they block the heavy moist air traveling eastward 5 form the Pacific Ocean. Lighter 6, drier air passes over the mountains. Until people intervened with irrigation and farms, only grass could grow on the dry, windy plain. In fact, we can divide the Great Plains into three zones. In the west, where it's driest and windiest, the grass is very short. In the eastern zone, there's more rain and grass grows as high as 360 centimeters. In the middle third, there's a mix of grass species that grow to an intermediate height.


n.地面,地形,地图
  • He had made a detailed study of the terrain.他对地形作了缜密的研究。
  • He knows the terrain of this locality like the back of his hand.他对这一带的地形了如指掌。
n.沉淀,沉渣,沉积(物)
  • The sediment settled and the water was clear.杂质沉淀后,水变清了。
  • Sediment begins to choke the channel's opening.沉积物开始淤塞河道口。
冰河,冰川( glacier的名词复数 )
  • Glaciers gouged out valleys from the hills. 冰川把丘陵地带冲出一条条山谷。
  • It has ice and snow glaciers, rainforests and beautiful mountains. 既有冰川,又有雨林和秀丽的山峰。 来自英语晨读30分(高一)
n.草原,牧场( grassland的名词复数 )
  • Songs were heard ringing loud and clear over the grasslands. 草原上扬起清亮激越的歌声。 来自《现代汉英综合大词典》
  • Grasslands have been broken and planted to wheat. 草原已经开垦出来,种上了小麦。 来自《简明英汉词典》
adv.向东;adj.向东的;n.东方,东部
  • The river here tends eastward.这条河从这里向东流。
  • The crowd is heading eastward,believing that they can find gold there.人群正在向东移去,他们认为在那里可以找到黄金。
n.打火机,点火器;驳船;v.用驳船运送;light的比较级
  • The portrait was touched up so as to make it lighter.这张画经过润色,色调明朗了一些。
  • The lighter works off the car battery.引燃器利用汽车蓄电池打火。
学英语单词
-arian
abnormality
additional entry
affinated sugar
ahmadu
all risk clauses
arsenic halide
automatic shutting-down
ball charge
bathycongrus retrotinctus
bernoulli law of large numbers
Bowman-Heidenhain theory
British gum
burlier
capacitive amplification system
carrier sense
casting and blading of materials
Cauas
coagulation treatment
compensatory errors
coolas
corporation sites
cost-effective analysis
cowke
crenulatin
crust breaking hammer carrier
danya
dazed and confused
dermoblast
detection charge
digital evaluation of measured value
draft proposal
dript
emparel
European network
evidential item
first internode length
genogram
genus Spermophilus
glass-ceramic
Gorakhpur
haggais
Halley's comet program
hand fid
heat curing system
hematite type microcrystalline glaze
high-hat
Holmestrand
homeless people
hyperphysemia
inclr
induction phase shifter
inhomogeneous coating
isis
just identified parameter
Kolwezi
koomis
lignin decomposing fungi
lobulus quadrangularis posterior
lock chamber water stage recorder
low water spring tides
loxoconcha nozokiensis
manulife
marine agency
milk spot liver
monthly transport plan
on general release
one-and-one
palisade layer
partial verdict
past performance standard
peel sight
PER/VAC
phenakites
photosynthetic oxygenation
planar double-diffused transistor
plebisitum
prorenal
quick make-and-break switch
Quonset huts
radio dermatitis
rancors
recking
Salix capitata
scatolias
schizoid type
separating cone
serum bactericidin
setting fire
Sikeli
sirets
Suviana, L.di
tail wheel bumper
turband
unchasteness
vacuolar degeneration of odonto-blastic layer
vascular myeloma
water-power station
whrrr
xion
yokelines
zero tolerance