音标:[ˈekəʊˌsɪstəmz] ;
n. <生>生态系统( ecosystem的复数形式 )
n. a system formed by the interaction of a community of organisms with their physical environment

Broadcast: Jan 16, 2003 Experts say one of the world's most feared, but misunderstood, creatures is under 2) assault by fishermen. A new study of all types of sharks finds that there are fewer of them

发表于:2018-12-08 / 阅读(162) / 评论(0) 分类 VOA2003(上)-科技先知

Report: Ecosystems More Stressed Than Ever When Super Storm Sandy ravaged the U.S. East Coast and inundated New York City in late October, many wondered if such extreme weather events might be linked to climate change, the gradual warming of the plan

发表于:2018-12-08 / 阅读(247) / 评论(0) 分类 VOA标准英语2012年(十二月)

Last week, tens of thousands of gallons of sewage gushed into urban streams in Baltimore, because of leaky pipes and flooding rains. And when that happens, it's not just organic matter and microbes that get flushed into aquatic habitats. It's drug re

发表于:2018-12-24 / 阅读(141) / 评论(0) 分类 2016年Scientific American(八)月

From NPR News in Washington, I'm Lakshmi Singh. A radical Sunni Muslim cleric born in the US is urging religious scholars to promote holy war against American and Israeli interests in the Middle East. NPR's Soraya Sarhaddi Nelson is in Cairo and repo

发表于:2019-01-08 / 阅读(149) / 评论(0) 分类 2010年NPR美国国家公共电台11月

Lonely bug NB: This is not an accurate word-for-word transcript Dima:Hello and welcome to this edition of 6 Minute English with me, Dima Kostenko Rebecca: and me, Rebecca Byrne. Dima:Today we'll have some useful words and phrases used in science and

发表于:2019-01-10 / 阅读(192) / 评论(0) 分类 六分钟英语

Severe Drought, Wildfires Threaten Water Resources This is Valles Caldera. Actually, it's the giant mouth of a dormant super volcano that last erupted 40,000 years ago. In the millennia since then, the terrain developed high-elevation forests, of abu

发表于:2019-01-13 / 阅读(248) / 评论(0) 分类 VOA标准英语2012年(一月)

AGRICULTURE REPORT - Study Warns of Risk to Seafood Supplies in World's OceansBy Jerilyn Watson Broadcast: Tuesday, November 14, 2006 This is the VOA Special English Agriculture Report. A study has wa

发表于:2019-01-30 / 阅读(156) / 评论(0) 分类 2006年慢速英语(十一)月

Topic: In some countries, parents expect children to spend long time studying both in and after school, and have less free time. Task: (You may spend 40 minutes on this task, and write a minimum of 250 words) Do you think it has the positive or negat

发表于:2019-02-09 / 阅读(198) / 评论(0) 分类 雅思英语

SECTION 1 Time - 30 minutes 38 Questions Directions: Each sentence below has one or two blanks, each blank indicating that something has been omitted. Beneath the sentence are five lettered words or s

发表于:2019-02-13 / 阅读(165) / 评论(0) 分类 实用英语

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发表于:2019-02-20 / 阅读(250) / 评论(0) 分类 加州语文教材California Treasures G3
学英语单词
a plump lie
adularia-albite series
all the closer
anemia in pregnancy
automatic drafting table
babies'
barrier complex
basal pinacoid
behavioral strategy
bespangle
Bethune,Mary McLeod
biphase signaling
bird ring
boat boy
bononcinis
carbodynamite
Cardamine arisanensis
cattle-rearings
crossed cylinders
de-fense
Dictyoestheria
domestic television
donkey derby
dose-maximalis
drag theory
dummy terminator
ealderman
Englishisms
experimental pedagogy
explicably
explicit interest
faughey
final clause
flashfloods
free bond
frog skin
general adaptation syndrome (g.a.s)
globe-news
gortex
grande toiette
hemorrhaging
in house research program
inclination dip
inin
inlet valve chest
isochronous pendulum
Jedi Masters
juan manuel
kapok life jacket
Kosovo, Battle of
Landolt's broken ring chart
limk
lyotropic number
mail carriers
marwell
metaconversation
Midnight Munchies
miniature fuse
monoacids
monoinfection
moon bags
musticate
naval gunnery
netting fibers
new star
no air
non-repudiation of delivery
nonrisk after discharge
number of threads per unit length
oceanites oceanicuss
order sth in
park-way
peak dark current
personal hotspot
petaloidy
pixel group processing
pressure proximity fuze
printed wiring backpanel
quiescent region
radical group
real-time operation on-line
Roman square capitals
San Demetrio Corone
sand dune vegetation
second sound carrier
septuple
siderography
sitta carolinenses
snub-noseds
social changes
strictly inductive limit
sulfur rain
superior fascia of urogenital diaphragm
sweep device
tack trice
two-aside network
upvotes
ustilago avenae (pers.)roster.
very high frequency omnidirectional radio range
vijaya
wave-cut bench of levee
WT