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(72) / 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(164) / 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(76) / 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(79) / 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(106) / 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(160) / 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(92) / 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(116) / 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(90) / 评论(0) 分类 实用英语

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发表于:2019-02-20 / 阅读(157) / 评论(0) 分类 加州语文教材California Treasures G3
学英语单词
adjusted stock price average
alder flycatcher
amplify
ancientries
antagonistic interest
anticountermeasures
Austin,John Langshaw
axillary lymph sac
B position
backing sand
barbette
barthelemy
basement waterproofing
be coincident with
beveling lever
body cameras
brake noodle
breeching gas
CASEP
Chalaua
chlorition
containment procedure
cotyledonary placenta
defect of ear lobe
delirium nervosum
diddlin'
ding-a-lings
direct laryngoscopy with dilatation
discharge hose
dry sand molding
dutch case-knife beans
farthing dip
fighteress
fleche distance
from mouth to mouth
fuel inlet needle valve
General George Custer
Gorbachyov
gravitator
gynotermon
harpiliopsis beaupresii
hepatogenous
housing estate
incineration vessel
ioka
jerker bar
limiscala lyra
low-affinity
loxodromic line
magnetic printer
main bang suppression
marganotum
matter dominated era
method of electro-mechanical analogy
mingler
mining electrical apparatus for non-explosive atmospheres
nebbech
neoethnicities
no-load running test of tanker
nonimitative
normal electrocardiogram
normal law of composition
nymphaea
oligonucleosomal
optic flow
orchard garden
ordnance checkout room
orthogonal system
oven chamber
pendular movement of mediastinum
poroelastic
posting field
preapplying
precipitate
preengineering technology
profaners
proportioning bin
racial-preference
recording bass
rotten-egg
runnels
rutates
schnier
self dump sulky rake
Shastri, Lal Bahadur
shrinking disease
sj?gren's syndrome
Skikda, G.d'
sounding
source level symbolic debugger
spline key
steady-state system
Tanda, Dép.de
three-strip colour camera
time-invariant regulator
trigonum retromolare (mandibul?)
underwater Doppler navigation
vasoconstrictives
virginica Chionanthus
waspily
whomel
wind-worn