时间:2018-12-27 作者:英语课 分类:英语时差8,16


英语课

Some people prefer clay tennis courts, others like grass. Yael and Don discuss the difference on this Moment of Science. Y: Hey Don, what do you say to a game of tennis later? D: Sure thing, Yael. But it has to be a clay court, okay? Y: But the grass courts are so close by. Why clay? D: I prefer clay because I'm able to slide in more easily for a shot, not to mention that the ball moves slower. Y: Why is that? D: Clay courts are covered with a layer of fine sand. This sand is slippery 1 enough for a player's shoes to slide around, but not so slippery that he or she is likely to slip and fall. This has to do with the shape of the sand. If it were perfectly 2 spherical 3, players would be slipping out of control. The sand on clay courts, however, has pointy bits with rounded ends. This same sand, though it allows the player to mover faster,slows down the motion 4 of the ball. This is because the cloth of the tennis ball captures 5 and drags sand as it hits the court. Y: If clay courts are so much easier to play on, then why do professional tennis players even use them? Wouldn't they want more of a challenge? D: It's not so much that one is easier than another. It really depends on the player. And good players know to adjust their serves according to the surface they're playing on. If it's grass, they serve as fast as possible. If it's clay they slow down the serve in order to put more spin on the ball. Both serves are difficult to return.



1 slippery
adj.滑的;油滑的,狡猾的,不可靠的
  • We found it very slippery under foot.我们感到地上很滑。
  • Mind out,the steps are slippery!注意,台阶很滑!
2 perfectly
adv.完美地,无可非议地,彻底地
  • The witnesses were each perfectly certain of what they said.证人们个个对自己所说的话十分肯定。
  • Everything that we're doing is all perfectly above board.我们做的每件事情都是光明正大的。
3 spherical
adj.球形的;球面的
  • The Earth is a nearly spherical planet.地球是一个近似球体的行星。
  • Many engineers shy away from spherical projection methods.许多工程师对球面投影法有畏难情绪。
4 motion
n.打手势,示意,移动,动作,提议,大便;v.运动,向...打手势,示意
  • She could feel the rolling motion of the ship under her feet.她能感觉到脚下船在晃动。
  • Don't open the door while the train is in motion.列车运行时,请勿打开车门。
5 captures
俘获( capture的第三人称单数 ); 夺取; 夺得; 引起(注意、想像、兴趣)
  • King Arthur himself captures the beast and cuts off its head. 亚瑟王亲自捉住怪物,并砍下它的头。
  • His book captures exactly the ethos of Elizabethan England. 他的书准确地描绘了英国伊丽莎白时代的风土人情。
学英语单词
AAGC
Aeschynomene americana
Allium schoenoprasum L.
amalgam plugger
application-development language
artificial stocking
bandage gauze
bat ribbon
binary synchronous device data block
bind-days
boysen berry
Brissaud's dwarf
chemical anticarcinogenic drug
chemoconvulsant
cherryville
Chrysomelidae
concolor
counter sample
cupids
dichloramine
disodic alkaliine
drill-sharpening machine
Echogynography
ecotonal
electrochemistry at liquid-liquid interface
electronic sign
Entale
extraneous term
fenoxazoline
fine ream
foamed polystyrene chaplet
garage shop
genus epipactiss
genus Sagina
gleewoman
haroutounian
heteropolyanion
homotopy type invariant
hot-finished material
Idb-1016
idea champions
incomplete compaction
injurious weed
isolar
jet cutting car
junta
ketchuppy
leptosols
load bearing characteristic
magnetization curve
medicinal perfume
methyl-1-testosterone
Midgard, Midgarth
mikester
military characteristics
monkey bread
moon trefoils
motor timer
mulesing
multiple-reclosing breaker
nuclear-level density
off-set seismic operation
optical fiber source
oral traditions
overfarm
overparameterize
oximctry
parachute troops
partial cracking
piston ring groove cleaner
Ponte di Legno
portal-type frame
pre-established harmony
quicktongued
ranque
rascally
salvage and salvage charge
sharpness of vision
Ship's Sinking
sovann
spiroplasma
Spy Wednesday
stamate
teleprocessor
Theilman
thiocolchicine
thread fasteners
tibetan high
Tiedemann's nerve
to pop the question
Transdanubia
trial by media
unstainable
vapor compression refrigerating machine
vertimeter
VWAP
Waddingworth
West Midland
wet snow
wet-chemical technique
white walnuts
wood pattern