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(251) / 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(336) / 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(209) / 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(239) / 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(346) / 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(350) / 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(215) / 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(313) / 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(268) / 评论(0) 分类 实用英语

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发表于:2019-02-20 / 阅读(336) / 评论(0) 分类 加州语文教材California Treasures G3
学英语单词
acoustic gramophone
agnomens
American winterberry
Anderson-Fabry disease
aneurysmal hematoma
angionoma
Annamocarya
artificial intelligence (AI)
backchain
beziques
Bohler splint
bruise trimming
cactus alkaloid
cameleers
catch on to
chemical equations
child of shame
cholangitis lenta
cholestyraminum
coincidence (-counting) rate
complete text
coreceptor
day tank
dead-fall
delivery of documents against acceptance
distribution of plant
Eastman Kodak Co.
echelon spectrograph
electric-transmission
equivolumnar wave
error of direction
exhaust-gas disposal
feminizers
Fkey
flabbergasters
flameproof dry-type transformer
fuse plow
geologic time table
graphic telluriums
Guemappe
hang river
heterofascism
hypoptilum
ignore the facts
individuism
ingluvial
insert cone
internal edge angle
JINS
kagumo
lactation
Langmuir plasma frequency
law enforcement agencies
liegnitz (legnica)
ligamenta intercargea volaria
Lobus inferior pulmonis dextri
mang
meissner
metropathia hemorrhage
murray mania
myxomatous myoma
nitches
Nonne-Milroy-Meige(syndrome)
North Foreland
orgyn
palm-leaf
petroleum resources
pidonia hohuanshana
pin-tailed sandgrouse
portal type implement carrier
preparatory culture
pubkeeper
put in a good word
reky
Retuerta de Bullaque
roncaglioloes
sapor
scopolamine methylbromide
sedentarised
spitbraais
squint at
ST_controlling_being-based-on-or-depending-on-something
starter drive
stellar tracking telescope
supercouple
swaddling bands
system, turnkey
take her place
tandoor
taylorsville
tetraclitella divisa
tevas
Thoma's ampulla
throttling bar
tigris
ulex europaeuss
uofs
wildlands
Wringer Rolls
wtcs
Yasser Arafat