horse  场景分类

Thank you  it’s great to see so many of you interested in this series on survival in outer space
" L6 m) p# S( KPlease excuse   camera we will being vediotaped  for the  local tv stations- {. G6 n9 f+ N7 s
Today I will talk about the most basic aspect of  survival   the spacesuit   when most  of you   imagine an astronaut   that is fisrt thing came to your mind  well without space suit  it would possible for us to be survive in space foe example outer space is vacuum it is no gravity or  air pressure  witjout protection  a body would explore  what’s more we ‘d cook in  the sun and freeze in the shade  with tempetures ranging from a toasty  3 000degrees above to cool 300 below zero Fahrenheit
& b: s; v  j7 v4 s% c6 D* KThe space suit that nasa has developed is a marvel  this photo enlargement here is a lifesize  image of an  actual space suit worn by astronauts on last space shuttle mission this part is a torso  it is made of seven extremely durable layers    this thick insulation protect against temperature extremes and radiation that is what they call a bladder of oxygen  that’s an in flatable sac filled with oxygen  to simulate asmospheric pressure  this bladder press against body with thee same force as the earth’s atmosphere at sea level  innermost layers provide liquid cooling and ventilation  despite all the layers  space is flexible allowing  free movement  so we can worlk ) v4 x8 Q8 P  M
Another really  sophisticated part of space suit is the helmet  I brought one along to show you 1 l: \, w, W6 w4 O2 q" y
Can I have a volunteer  to come and demonstrate , X) l4 N+ Y4 z$ e
今天     我完成任务   了

完成   9个的 2.5 个了  接近三分之一   加油  不远了

开始 了  今天的任务  地球科学

I glad you brought up the questions of investigations into tha makeup of earth interior
( {4 m: ]) C  o9 rIn fact  since  this is a topic of your reading assignment for next time let me spend few minutes od class talking about it there were several important discoveries in the early part of this century that help  geologists  develop more accurate   picture of  the earth interior+ z! p  r) d5 u4 @
The firet key discovery had to do with seismic waves   remember they are the vibration caused by earthquake well sciencetists  f ound  that they travel   thousands   of milms   through the earth interior  this founding enable  geologists  to study  interior   parts of the erath  you see these study  revealed  that this vibration  was two types   compression or p- wave  shear  s-wave  and  researcher has found   that p – wave t ravel through both liquids and solids   while s –wave travel only through  solid matter   
3 V* S6 B! d$ v6 B2 @( x/ b; r% MIn 1906a  british geologist discovered that pw slow  down at an certain depth    but kept traveling deeper  on th o h s –wave disappear or  were reflecked back   so he concluded that the depth marked the boundry Between solid  mantle  and liquid core depth three  years  l ater another boundary  was discovered  that between mantle and earth crust
$ N9 Q1 ~: M5 ~  S% R( N' j2 CThere are still a lot to be learn about the earth  f  geologists know that the core is hot  evidence of this is molten lava that flows out of volcanoes   But we  are still not  sure what the souce of the heat is
4 T5 X$ W: H/ A4 A' R接着 做   总体感觉较好  可能是写的 记的 方法改善, v9 O/ r, A: w) g5 u) ~. }
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[ 本帖最后由 走聪明 于 2008-1-16 16:42 编辑 ]

太多了  有点完不成的趋势   但没办法  只有 加油 了     谁叫我说了  保质  保量    不要为自己打折扣

还有一个 secret  听写 真的能延年益寿

加油哦^ ^
8 x( M  s  x9 L- s0 G3 I2 E8 _这样下去一定没问题的!!

The old canada road is a long lost trail between Canadian  province of quebec and  maine in the northeast corner of the united states  yes it is very lost  and finding it again is complex process that involved state of the art technology  how the location of road was pinpointed   was very interesting and now I will return to it as soon as   I have  given  you’re a little background information   the  road   was  becam in  1817 a few  years before  maine  even  became a state   at the time  quebec  was a major  market  for life stock   crops  and fish   so a road to quebec  was seen by officials in main as  necessary for trade  for about  20 years    the movement  of people  an g oods was mostly from maine to quebec  but  then reversed as thousands of Canadian immigrated to maine to escape poor crops a lack of job  the threat of disease  I think it was a  cholera epidemic      还有一半  这个

我为什么  光听写 不算跟读   都要花一个小时啊      听力实力不行啊