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(258) / 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(344) / 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(214) / 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(246) / 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(351) / 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(357) / 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(225) / 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(324) / 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(274) / 评论(0) 分类 实用英语

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发表于:2019-02-20 / 阅读(340) / 评论(0) 分类 加州语文教材California Treasures G3
学英语单词
4-fluoro-2-nitroanisole
a digit switch
acanthomytilus imperatae
Acmoheliophyllum
admit daylight into someone
advertize
affirm to
automatic relay calculator
Baron Friedrich Wilhelm Ludolf Gerhard Augustin von Steuben
behavior chain
bill and coo
brood cannibalism
Calmiren
cavillatory
chianti
chlamys inaequivalvis
ciliary groove
clarite
code-switched
CoMFA
coml.
competent income
completely metrizable space
compressibility of fluid
connection of circuits
contact voltage regulator
courtin
Cousinia thomsonii
cutting piler
disk coupling
dry-gulchings
enlarging machine
examination of document
exponential factor
export sale
family court
feering
fire patrol
fixed routing per call
free air delivery
freight transport
Fresnel integrals
give it to 'em upon the bounce
Hammett-Zucker postulate
hashkeys
heat treatment line
hematimetry
humanely
Ifergane
impact tension
incompass
inconsistence of geometrical construction
Jena-glass
ju-yung
Kambali
LHX
mono-N-dealkyl-diisopyramide
mooring post
morphean
multiple converter
muriqui
noise budget
oleum pimentae
overflow piping system
pattern sensitive fault
personal realism
perviousnesses
pionic atom
Polevoye
preadolescence
programmist
pull-behind
pulse-amplitude-modulated sample
rayda
ready - to - eat food
rolypolinesses
sacro-iliac strain
salespattern
San Joaquin R.
sapientia
sebag
self-service analytics
septoic
Sintuism
Spittal Pond
standard transducer
strip-card reader
superhigh pressure sealing
synopticss
talk-radio
telescopic energy-absorbing steering transmission shaft
temporary repair siding
therm(a)esthesia
thumb war
two-input switch
two-leaf
uv-light
Vedeno
vehicle body coordinate system
viaducted
wipe out
wood-milling machine