时间:2018-12-30 作者:英语课 分类:托福听力短文


英语课
(woman) To us, the environment in which fish dwell often seems cold, dark, and mysterious. But there are advantages to living in water, and they have played an important role in making fish what they are. One is that water isn't subject to sudden temperature changes. Therefore it makes an excellent habitat for a cold-blooded animal. Another advantage is the water's ability to easily support body weight. Protoplasm has approximately the same density 1 as water, so a fish in water is almost weightless. This "weightlessness" in turn means two things: One, a fish can get along with a light weight and simple bone structure, and two, limitations to a fish's size are practically removed.

Yet there is one basic difficulty to living in water --- the fact that it's incompressible. For a fish to move through water, it must actually shove it aside. Most can do this by wiggling back and forth 2 in snakelike motion. The fish pushes water aside by the forward motion of its head, and with the curve of its body and its flexible tail. Next, the water flows back along the fish's narrowing sides, closing in at the tail, and helping 3 the fish propel itself forward.

The fact that water is incompressible has literally 4 shaped the development of fish. A flat and angular shape can be moved through water only with difficulty. And for this reason, fish have a basic shape that is beautifully adapted to deal with this peculiarity 5.


n.密集,密度,浓度
  • The population density of that country is 685 per square mile.那个国家的人口密度为每平方英里685人。
  • The region has a very high population density.该地区的人口密度很高。
adv.向前;向外,往外
  • The wind moved the trees gently back and forth.风吹得树轻轻地来回摇晃。
  • He gave forth a series of works in rapid succession.他很快连续发表了一系列的作品。
n.食物的一份&adj.帮助人的,辅助的
  • The poor children regularly pony up for a second helping of my hamburger. 那些可怜的孩子们总是要求我把我的汉堡包再给他们一份。
  • By doing this, they may at times be helping to restore competition. 这样一来, 他在某些时候,有助于竞争的加强。
adv.照字面意义,逐字地;确实
  • He translated the passage literally.他逐字逐句地翻译这段文字。
  • Sometimes she would not sit down till she was literally faint.有时候,她不走到真正要昏厥了,决不肯坐下来。
n.独特性,特色;特殊的东西;怪癖
  • Each country has its own peculiarity.每个国家都有自己的独特之处。
  • The peculiarity of this shop is its day and nigth service.这家商店的特点是昼夜服务。
学英语单词
A. E. Kennelly
acarinium
attackman
bettelheim
bit strip
bothersome
bromo-mercuriphenol
bucksbaum
carbide precipitation
castanopsis delavayi franch.
Castillo de Bayuela
chalazodermia
chicken and ham sandwish
chocolate face
closed loop mode
compatible integrated circuit
congruential method
control trajectory
cosell falsus
cruciform core
cutenesses
deetz
disceyvous
doberman
drysse
dumping policy
effervescent granulation
electrostatic cathode ray
enter a bid
equivocal surface
featherly
filibuster
forthglided
fum
g.w.r.(gas-water ratio)
gollattscheck
impaction loss
ivaz
Jamnia
jar-proof
kit-fox
laminae intermuscularis
lattice pile
Ledebur's bearing metal
lippet
liras
management of science and technology
manticulate
margaric acids
maximum travel of boring spindle
Mayson L.
megadalton
messaging client
methine group
middleoftheroaders
modulation phase
monoplane flying fish
Nābū'ā
O1-constituent
offer ... to
optical time division multiplexing
original thought
outrageousness
over-tongued
oxygen mask
pelargone
pet parent
picrin
piston pump
plateletphereses
populus deltoidess
posterior thoracic nerve
poxviruss
preshredded
prospective earnings
provokement
quadrature phase splitting circuit
radii
recent times
sacramentized
scalariform duct
self-respectingly
selling warehouse
semifinished item
sender telephone
sisnsfsosrsmsastsisosns-s
sound field plotter
space programs
st. ambroses
stenosal
sue-sue
sumacoite
to learn by heart
towk
transmitter ready
unbalanced-throw screen
video recording rator
Vikingness
villasimiuss
welshofer
where you at
white petrolatum