序滤波器,相序过滤器

Editors note: This is the third episode of four-part series on verb tenses. Be sure to listen to part one and part two first. For VOA Learning English, this is Everyday Grammar. Today we are going to talk about the perfect verb tenses. Perfect tenses

发表于:2018-11-27 / 阅读(380) / 评论(0) 分类 2016年VOA慢速英语(十二)月

Section A [00:01.23]1. M: I haven't decided which subject to major in [00:04.96]physics or chemistry. [00:07.76]W: It isn't easy to choose,is it? [00:10.21]Q: What does the woman mean? [00:13.87]2. W: The map shows that this street goes downtown. [00

发表于:2018-11-29 / 阅读(151) / 评论(0) 分类 决胜四级听力必备

Section A [00:01.54]1. M: My grandpa died in 1978. I was 18 years then. [00:08.20]W: That means he would be 76 if he were alive. [00:11.49]Q: How old was his grandpa when he was dead? [00:14.45]2. M: Why are you going so fast? [00:17.53]Where are you

发表于:2018-12-01 / 阅读(171) / 评论(0) 分类 决胜六级英语听力

This is Scientific American's 60-Second Science. I'm Cynthia Graber. This will just take a minute. Its the time of year to take a look backand thats just what the journal Science did as they listed their most important breakthroughs of 2008. At the v

发表于:2018-12-02 / 阅读(96) / 评论(0) 分类 Scientific American(十二)月

图片 by Jason Marshall Its not often someone suggests that knowing some math could make you the life of the party, but thats exactly what Im going to do. Yes, a properly timed delivery of a few fun facts about the famed Fibonacci sequence just migh

发表于:2018-12-07 / 阅读(105) / 评论(0) 分类 数学英语

[ti:UNIT 7 Enjoy Your Hobby Lesson 56:Unit Review] [0:01.051]Unit 7 [0:02.631]Enjoy Your Hobby [0:04.894]Lesson 56: [0:06.943]Unit Review [0:08.907]I. [0:10.231]Building Your Vocabulary [0:12.963]A. [0:14.500]Fill in each blank with the proper word o

发表于:2018-12-10 / 阅读(112) / 评论(0) 分类 河北教育初中英语(初中起点)八年级上

But the HEPA filter for Olivers Vibe got dirty very quickly. And, it was not cleanableit was simply replaceable. When it turned filthy brown, Oliver went back to Target to buy a new filter. Oddly, Target sold the F15 belt for the Vibe, but not the fi

发表于:2018-12-11 / 阅读(94) / 评论(0) 分类 365个英语简短小故事

发表于:2018-12-12 / 阅读(48) / 评论(0) 分类 医务英语

This is Scientific American's 60-Second Science. I'm Steve Mirsky. Got a minute? The human genome was sequenced, and in the process of moving that forward the technology that was developed was incredible. And because of their efforts in human genome,

发表于:2018-12-24 / 阅读(135) / 评论(0) 分类 Scientific American(十)月

Describing Order and Sequence Patrick: Okay, your first task is to put all of these files in order. Maya: Wow, there must be hundreds of files in this storeroom. How am I supposed to organize them? Patrick: Create a basic filing system. Put things in

发表于:2018-12-27 / 阅读(95) / 评论(0) 分类 2014年ESL之商务英语

图片 by Jason Marshall Some math is functional. Some math is fun. And some math is simply stunning. If that last description sounds improbable to you, then today just might change your mind. Because now that weve covered enough ground, were going t

发表于:2019-01-02 / 阅读(183) / 评论(0) 分类 数学英语

From VOA Learning English, this is the Health Lifestyle report. In parts of India, it is not uncommon to see people wearing a mask over their nose and mouth. The capital, New Delhi, has some of the world's dirtiest air. The pollution was a call for a

发表于:2019-01-03 / 阅读(89) / 评论(0) 分类 2018年VOA慢速英语(一)月

This is Scientific American's 60-Second Science. I'm Steve Mirsky, got a minute? Neandertals were our closest relatives. And now we know a lot more about them. Because researchers have for the first time sequenced a complete Neandertal genomethat of

发表于:2019-01-08 / 阅读(99) / 评论(0) 分类 Scientific American(八)月

This is Scientific American's 60-Second Science. I'm Steve Mirsky. Got a minute? Robin Williams thought that the platypus was cobbled together by an inebriated deity: Lets take a beaver. Lets put on a ducks bill. Now we know how weird the platypus is

发表于:2019-01-08 / 阅读(100) / 评论(0) 分类 Scientific American(五)月

古埃及金字塔是奴隶制帝王的陵墓,最宏大的当为吉萨三座大金字塔。塔基呈方形,每边长230米,高146米,用230余万块巨石(每块平均重达2.5吨)垒成,国王墓室用一块400吨重的石板垒成。整体规

发表于:2019-02-01 / 阅读(69) / 评论(0) 分类 阅读空间

By Tabinda Naeem Washington, D.C. 21 May 2007 Two years ago, the National Academy of Engineering established the Grainger Challenge Prize for Sustainability. This $1 million award was designed to challenge the world's scientists to develop a practica

发表于:2019-02-03 / 阅读(131) / 评论(0) 分类 2007年VOA标准英语(五月)

BEIJING, Aug. 22 (Xinhuanet) -- Researchers have discovered how a human egg captures an incoming sperm for fertilization, paving the way to help couples suffering from infertility, according to media reports on Monday. An international team of resear

发表于:2019-02-08 / 阅读(105) / 评论(0) 分类 英语新闻

Listen to the schedule of a business trip. Fill in numbers l-8 to point out the sequence of the schedule. I'm leaving for Milan on the 7th of June. l'II arrive there on the 8th evening at about 7:OOpm. Then, l'II take a shuttle bus to the hotel. On t

发表于:2019-02-17 / 阅读(76) / 评论(0) 分类 英语听力练习题

Listen to the dialogues and write the correct sequence of l-6 as mentioned in the dialogues. A:How do I search books from the computer? B:First, key in your PIN number. Then, it goes to the Library's Homepage. Then, you can choose any way you want to

发表于:2019-02-17 / 阅读(60) / 评论(0) 分类 英语听力练习题

Thank you for being here,Fareed.Nice to have you on the show. 多谢你抽空前来 法里德 很高兴你能来上节目 Let's get started first with your background.I do think I know a lot about you. 首先聊聊你的背景 我觉得我很了解你

发表于:2019-02-23 / 阅读(64) / 评论(0) 分类 柯南脱口秀
学英语单词
8-tracks
abderrahman
almucanter
Anno.
apron-string hold
Arctocyonidae
attorney's fee
autoricks
beede
bilingual-education
boil dry
box kiln
Brieger's cachexia reaction
calcinus seurati
Calonne-Ricouart
centric ring
cerebrospinal syphilis
Colphos
complicated nuclear effect
control breakpoint
curbstoner
cytocannibalism
darcys
demounted
distillation rube
donah
drain cap
drop a bucket into an empty well
Elgin Down
erbium base alloy
excubation
express to
Florence's tests
fluidization number
Frekentine
furanopetasitin
glomerulate
hang up on sb
immoulds
labyrinthlike
Liddington
lithium tetraborate
Lloyd B.
love taps
Macuze
maximum possible flood
medicinal sensorineural deafness
monochromasies
multiple-target system
nettiest
o'sheas
OPISTHOPROCTIDAE
Oued Laou
Parcourse Fitness Circuits
part-load transshipment station
peace processes
peak-holding circuit
pennies
pentams
phosphoric acid manufacture
physics package
pilot fish
pincette type seedling puller
pneumatic steelmaking
power pipe cutter
presagings
proscripation
pulmonian
punch-bowl
punctuated equillibrium
quadriads
regenerated carbon
retarding potential method
Rheum likiangense
rotor plane
salmonella-free
sauromalus obesuss
sematheist
series half-bridge rectifier
ship's medical officer
shunting control position
skolite
spiraled duct
staining wood
steamboats
sternocleidomastoid muscles
still frame
succinate thiokinase
sumach extract
technological imperative
thermostatic iron
three-stage air compressor
tray flatness
underoptimization
ununderstandable
urban redevelopment work
vapour phase thermal cracking
variable volume
vertical market
vulcanization activator
walks off
yellow salsifies