e英语教材3unite3

There are many forms of life on Earth, including human beings.  Life exists in  a variety of   condition s. Some forms of life live in a  watery environment , like the oceans. Other forms of life can be found in very dry areas like  deserts . However, for any form of life to  exist , conditions must be right. When conditions are not right, that form of life will become  extinct . To become extinct means to  die out  completely. Conditions must be right for life to exist. Millions of years ago, there were forms of life that  no longer  exist. When conditions changed, these forms of life died out.  One extinction event happened about 250 million years ago.  This was the largest extinction event of all time.  Many forms of life became extinct.  96% of all life in the oceans died out.  Most  insects  also became extinct. This event happened  over a period of several million years. The causes of this extinction event are still unknown . Possible causes include  large volcanic eruptions  and  global warming. Some scientists believe that there were several causes.  They believe that  a series of  events caused the extinctions. Scientists are working to better understand what really happened. In modern times we humans face changing conditions.  For humans to live, we need clean air and clean water.  Pollution is now a growing problem around the world.  Pollution poisons the air and water that we depend on.  Polluted air makes people sick and afraid to go outside.  Polluted water poisons our food  supply . As a result, we never know which foods are safe to eat.  Human beings cannot live in a poisoned environment.  Therefore , pollution is a  major threat  to our  existence . Humans need temperature to be  in   a comfortable range . To be in a comfortable range means to be  neither  too hot  nor  too cold. With global warming, global temperatures are rising.  As temperatures rise,  the polar icecaps will melt . As the polar icecaps melt,  ocean levels will rise. Areas of some countries will soon be under water.  People will be  forced  to  relocate  from  flooded  areas. In nature , even small changes can sometimes have large  effect s. It’s difficult to  predict  what’s going to happen. The  entire ecosystem  that we depend on is changing. Some of these changes are  irreversible . Irreversible changes cannot   be undone . Let’s hope that humans are smart enough to understand how the world is changing.  With more understanding, we can make better choices about what to do. We can face the  challenge s of the pollution and global warming. We need to do this before it’s too late.  This planet Earth is our only home and we need to protect it. Mammal s are covered by hair or  fur , have a backbone and are warm-blooded. All female mammals produce milk for their young. Reptile s are covered by  scale s, and include snakes,  lizard s and  turtle s. Reptiles have a backbone and are cold-blooded, which means they often  rely on   external sources of heat . Birds are covered by  feathers  and are warm-blooded. Most birds can fly and many types of birds  migrate   great distances. Most  insect s such as  ant s and  bee s have a small, 3-part body with 3 pairs of legs. Some insects, like mosquitoes ,  spread diseases that cause the deaths of many humans. Unlike  animals, plants get the energy that they need from the sun. Plants  convert  light energy along with  carbon dioxide  and water into chemical energy. Most mammals live on land, but some live in the sea. Insects don't have a backbone, and most are cold-blooded. Scales and rulers are used to measure weight and length. Units of weight includes kilograms and pounds and units of length includes centimeters and inches. These instruments are used to observe very large and very small objects. Telescopes are used by astronomers and microscopes are used by biologists and doctors. These appliances are used in the kitchens of almost every home. Stoves are used to heat food and refrigerators are used to keep foods cool or cold. Household tools like these, are used to build and repair things. Hammers are used to pound in the nails and screwdrivers ar]e used to turn a screw.                   Forms of Life  生存的形式 Mammals are covered by hair or fur, have a backbone and are warm-blooded.哺乳动物被毛或毛皮覆盖，有脊椎骨，是温血动物。 All female mammals produce milk for their young.所有雌性哺乳动物都为幼崽产奶。 Reptiles are covered by scales and include snakes,lizards and turtles. 爬行动物被鳞片覆盖，包括蛇、蜥蜴和乌龟。 Reptiles have a backbone and are cold-blooded, which means they often rely on external sources of heat.爬行动物有脊椎骨，是冷血动物，这意味着它们经常依赖外部热源。 Birds are covered by feathers and are warm-blooded.鸟类被羽毛覆盖，是温血动物。 Most birds can fly and many types of birds migrate great distances. 大多数鸟会飞，许多种类的鸟迁徙距离很远。 Most insects such as ants and bees have a small, 3-part body with 3-pairs of legs.大多数昆虫，如蚂蚁和蜜蜂，都有一个由三部分组成的小身体和三对腿。 Some insects, like mosquitoes, spread diseases that cause the deaths of many humans.有些昆虫，如蚊子，传播导致许多人死亡的疾病。 Unlike animals, plants get the energy that they need from the sun. 与动物不同，植物从太阳中获得它们所需要的能量。 Plants convert light energy, along with carbon-dioxide and water, into chemical energy.植物将光能、二氧化碳和水转化为化学能。 Scales and rulers are used to measure weight and length.天平和尺子是用来测量重量和长度的。 Units of weight include kilograms and pounds, and units of length include centimeters and inches.重量的单位包括千克和磅，长度的单位包括厘米和英寸。 These instruments are used to observe very large and very small objects. 这些仪器用于观察非常大和非常小的物体。 Telescopes are used by astronomers, and microscopes are used by biologists and doctors.天文学家使用望远镜，生物学家和医生使用显微镜。 These appliances are used in the kitchens of almost every home. 几乎每个家庭的厨房都使用这些电器。 Stoves are used to heat food and refrigerators are used to keep foods cool or cold.炉子用来加热食物，冰箱用来冷藏食物。 Household tools like these are used to build and repair things. 像这样的家用工具是用来建造和修理东西的。 Hammers are used to pound in nails and screwdrivers are used to turn as crew.锤子用来敲钉子，螺丝刀用来拧螺丝。 Rulers are used to measure length. Telescopes are used by astronomers, and microscopes are used by biologists and doctors.do you know what  day it is today? what do you mean? it is a special day? oh so you don‘t remember. remember one. what's so special. its our anniversary. we start  a dating a year  today oh really ？sorry  what you think of this oh its a necklace  do you like it  yes i do.its lovely and its special light heart may i put it on   no,let me do it so you did remember of course i remember its a very special day for both of us i have something for you too you do? yes but we have to wait until later oh i cant wait  tell me what it is can you guess what it is? could you give me a hain we went there six month ago oh you  yes are you excited? yes that's ture i also remember the deserver do you ? wa the mune looks great and a specialist fish yes it looks good  yes but this prise is too high dont you think? yes they are a bit too high but dont you think im worth it  let's enjoy ourselves ok if you put that way  let see if we can get a table im glad you have your credit card i sure hope the food is good staff worrying Life exists in a variety of conditions we started dating a year ago todayThat restaurants looks nice. Yes, but it looks expensive. Let's go in and look at the menu. Wow the menu looks great, especially the fish. Yes, it looks good, but look at those prices. Let's try someone else. Sometime it's okay to spend a little money. Yes, but this prices are bit too high. Don’t you think? Yes, they are a bit high.  But don't you think I am worse it.  Let's enjoy ourselves. Ok if you put that way.  Let’s see if we can get the table. I’m glad you have credit card. I sure hope the food is good. Stop worrying.  Let’ just enjoy he is worried about spending so much money. he's chinese i am sorry  but our  offices are closed. he needs to eat fewer  exercise more. please call bike  during business hours. conditions must be right for left to exist. he remembered that  today is their unversary. human beings  cannot live in a posion veryme let's  go  in and look at the menu  the menu looks great and expecialy the fish i sure the hope is good the  this event happend pollution is now a growing problem mammals are coverd peptiles are covere most birds can fly role play that restaurant looks  let's  yes  sometimes  yes they are  i am glad  stop worry