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
adder tube
aging time
appallest
archaicizing
arteriolar nephritis
at tinah
Athesmia
automatic screen printing machine
autotracking error
baruti
belt-gear reduction type
Brunswick Junction
Carthusian order
Castellanella pulmonalis
ch? gaku (japan)
Chachauda
computerized market timing system
control of ship
cotunite
cystis ductus epoophori longitudinalis
damage from oil pollution
day-release
dead time losses
defaced coins
delayed disclosure
diffusion welding
distribution chamber for forced hot air
double-axle bogie car
ecological capacity
engraving-machine
enthalpy-composition chart
epilesional
Eric the Red
fantasia
favourable conditions
first bases
footprinting assay
functional form of linear function
Gibbs rule
grandala
group carry
Helenium autumnale
heroic meters
high rank coal
Hurwitz formula
hyperparametric
I should smile
in its wrong perspective
Indian almonds
interest-free grace period
Kawashiri-misaki
kirchoff
line lapped
lobaria lobulata reagens
lungan
magnetopneumogram
main detonating line
medicated pencil
medium-curing asphalt
mixing accuracy
monsterously
multi-spindle machining
nature-versus-nurture
necrobiotic xanthogranuloma
needler
negative pressure protection system
new mysterianism
olive-drabs
outofsquare
palaeoecological picture
paracyte
permo carboniferous system
pha
phone - in
port-call
post-object
pressure strip
printer's felt
pulse-frequency spectrum
punch and shear
qualilty management
recondense
rhynchoin
scroll ribbon
segmentization
shave through
shop-lifted
sidpas
static loading
surface heat transfer
tatenen
telegonidia
terminal curve
the inferno
the second order moment compensator
timber dimension
turritella
underpinning work
Vyselki
WASPization
welded suspending hook
zonohedron