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
.oogl
abbreviarist
alabam
alesis
aluminized mild steel
anti comet tail gun
be na
bear clique
bearing clearance
berg wind
bittersweet nightshade
black-headed
bliki
border warrant
bus tie link
charge of the light brigade
chiliads
construct on projection
contoured roll
counterphobia
country-houses
ctenomys talarum
data initiated control
dinucleotide
direct heat exchanger
disciplinary dismissal
displaced persons
dissatisfyings
Dowche
Elmwood Park
embodiers
entellus
fail-safe facility
floating spleen
franchises licensing
fright night
get in sour
golden years
ground water run off
gwynneth
haydenite
heorot
in house facility
ingoes
intraventricular foreign body
introvision
iterative evolution
james cleveland owenss
laser hole drilling
lead dithiofuroate
logotherapists
Lorado
lose one's breath
luminance coefficient
magnetophoreses
mentzelia lindleyis
microtrajectories
mire vegetation
n-ple point
normal legal safeguard
normal thickness on constant chord
ophiolitic complex
oski
part-task simulator
path of total eclipse
pell-mell structure
performance management specification
photodepletion
pintados
pirozhkis
plant budget
plug in type fuse
Polyalthia lancilimba
preset control line
prospective yield
Puyango, R.(Tumbes, R.)
quaffs
railway center
recovery prediction
refurbishment of existing buildings
Samkhret' Oset'i
San Pietro
screw down
seagulled
set criteria
shamable
shameness
sight tracking line
silk market
stadium eruptionis
stutting
takes up with
tibial crest
tolerative
undefined length block
ungiving
unnapped
verb-object
volcano-karst
volume of soil liquid phase
wet-bulb depression
zederone