Have you ever wondered?1. Why do airplanes ta...

Have you ever wondered?

Why do airplanes take longer to fly west than east?

It can take five hours to go west-east from New York(NY) to London but seven hours to travel east-west from London to NY. The reason for the difference is an atmospheric phenomenon known as the jet(喷射) stream. The jet stream is a very high altitude wind which always blows from the west to the east across the Atlantic. The planes moving at a constant air speed thus go faster in the west-east direction when they are moving with the wind than in the opposite direction.

What would happen if the gravity on Earth was suddenly turned off?

Supposing we could magically turn off gravity. Would buildings and other structures(建筑物) float away? What happened would depend on how strongly the things were attached （附着）to the Earth. The Earth is moving at quite a speed, moving at over a thousand miles per hours. If you turn something around your head on a string（细绳）, it goes around in a circle until you let go of the string. Then it flies off in a straight line. ‘Switching off’ gravity would be like letting go of the string. Things not attached to the Earth would fly off in a straight line. People in buildings would suddenly shoot upwards at a great speed until they hit the ceiling. Most things outside would fly off into space.

1.What information can we get from the first passage?

A.It is jet stream that affects how fast airplanes fly

B.Planes go slower when they are moving with the wind

C.It takes more time to fly from NY to London than from London to NY

D.The yet stream always blows from the east to the west across the Atlantic

2.The word “shoot” underline in the 2^nd passage probably means “          ”

A. send for        B. move quickly    C. come out     D. grow quickly

3.It can be inferred that without gravity  .

A. buildings and other structures would float away

B. trees and buildings would not easily fly off

C. something around your head would not fly away

D. everything outside buildings would fly off into space

高二英语阅读理解中等难度题查看答案及解析

Have you ever wondered?

1. Why do airplanes take longer to fly west than east?

It can take five hours to go west-east from New York (NY) to London but seven hours to travel east-west from London to NY. The reason for the difference is an atmospheric phenomenon known as the jet(喷射) stream. The jet stream is a very high altitude wind which always blows from the west to the east across the Atlantic. The planes moving at a constant air speed thus go faster in the west-east direction when they are moving with the wind than in the opposite direction.

2. What would happen if the gravity on Earth was suddenly turned off?

Supposing we could magically turn off gravity. Would buildings and other structures float away? What happened would depend on how strongly the things were attached to the Earth. The Earth is moving at quite a speed, moving at over a thousand miles per hour. If you turn something round your head on a string, it goes around in a circle until you let go of the string. Things not attached to the Earth would fly off in a straight line. People in buildings would suddenly shoot upwards at a great speed until they hit the ceiling. Most things would fly off into space.

1. What information can we get from the first passage?

A. The jet stream always blows from the east to the west across the Atlantic.

B. Planes go slower when they are moving with the wind.

C. It takes more time to fly from NY to London than from London to NY.

D. It is the jet stream that affects how fast airplanes fly.

2. The word “shoot” underlined in the 2nd passage probably means“ ______”.

A. send for 　　 　 B. come out

C. move quickly　　 D. grow quickly

3. It can be inferred that without gravity _________.

A. trees and buildings would not so easily fly off

B. buildings and other structures would float away

C. something around your head would not float away

D. everything outside buildings would fly off into space

4. Where can we most probably read this text?

A. In a student’s book　　　　　　　　 　 B. In a short story

C. In a travel magazine　　　　　　　　　 D. In a research paper

高二英语阅读理解中等难度题查看答案及解析

Have you ever wondered why there are so many skin colors in the world? Do you know why people living in particular areas usually have a certain color? Biology and history are the two reasons for this.

Skin contains something called melanin, which determines a person’s skin color. The more melanin a person has, the darker his or her skin will be. The amount of and the production of melanin are controlled by genetics, but can be affected by other things, such as sunlight. If a person lives in a place with less sunlight, a person’s body will produce less melanin, making the skin lighter.

Skin color is also affected by another source ---- vitamin D. humans all need vitamin D to build bones. People can get it by eating foods such as fish and milk, or from sunlight, so sunlight absorbed by melanin cannot be used for vitamin D production. Therefore, a dark—skinned person will produce less vitamin D than a light—skinned person when they received the same amount of sunlight.

The connection between vitamin D production and skin color is clear when we look at evolution. The earliest humans lived in Africa, their dark skin produced less vitamin D because of their dark skin. As a result, their skin made less melanin, so they could get enough sunlight to produce vitamin D. their skin gradually got lighter and they lost hair. Now, people living in areas with strong sunlight like Africa, have darker skin, while people living in other areas have lighter skin. The exception to this is the Inuit, who live in a place with little sunlight, but have dark skin because they eat a lot of fish and have enough vitamin D.

Evolution has given us a rainbow of skin colors. Humans have always had melanin to determine our skin color. What has changed through history is the environment where we have lived. This has in turn changed our melanin production, and eventually, skin color.

高二英语其他题中等难度题查看答案及解析

Have you ever wondered why there are so many skin colors in the world? Do you know why people living in particular areas usually have a certain color? Biology and history are the two reasons for this.

Skin contains something called melanin, which determines a person’s skin color. The more melanin a person has, the darker his or her skin will be. The amount of and the production of melanin are controlled by genetics, but can be affected by other things, such as sunlight. If a person lives in a place with less sunlight, a person’s body will produce less melanin, making the skin lighter.

Skin color is also affected by another source ---- vitamin D. humans all need vitamin D to build bones. People can get it by eating foods such as fish and milk, or from sunlight, so sunlight absorbed by melanin cannot be used for vitamin D production. Therefore, a dark—skinned person will produce less vitamin D than a light—skinned person when they received the same amount of sunlight.

The connection between vitamin D production and skin color is clear when we look at evolution. The earliest humans lived in Africa, their dark skin produced less vitamin D because of their dark skin. As a result, their skin made less melanin, so they could get enough sunlight to produce vitamin D. their skin gradually got lighter and they lost hair. Now, people living in areas with strong sunlight like Africa, have darker skin, while people living in other areas have lighter skin. The exception to this is the Inuit, who live in a place with little sunlight, but have dark skin because they eat a lot of fish and have enough vitamin D.

Evolution has given us a rainbow of skin colors. Humans have always had melanin to determine our skin color. What has changed through history is the environment where we have lived. This has in turn changed our melanin production, and eventually, skin color.

高二英语阅读理解中等难度题查看答案及解析

Have you ever wondered: What drives successful people? Take a look around and talk to your friends and seniors who are very successful, you will see all of them have adopted certain values which have proved vital for their success.

It is evident that successful people take initiative (主动性). When they find something needs to be done, they just do it instead of waiting. They believe that responsibility is taken, not given. They weigh immediately what has to be done and then do it with pleasure, thus strengthening their reputation.

Successful people are enthusiastic about the things they do, especially when they believe in what they are doing. They are motivated by their own satisfaction and the joy they get from doing their work. They work hard even when no one is watching and they throw themselves into their work.

They do not fear failure. Failures and disappointments in life are unavoidable. It is failure that teaches us much more than success. Successful people pick themselves up after a fall and try again with more determination and commitment and learn from each failure. They associate with those they can learn from and enjoy the company of those who appreciate their achievement.

Having good IQ often gets a person what he wants but it’s really the EQ that keeps him there and helps him enjoy a high reputation. Successful people are polite to everyone and treat others with respect. By giving respect to others, they command respect for themselves.

Another important quality of successful persons is that they never complain. It’s better to praise others and win favor with them. So instead of complaining about a situation, successful people always try to solve it.

To put it shortly, take initiative and be enthusiastic about them. Do not be afraid to fail, but get up and start again. When you do so, success will be just around the corner.

Title: What Makes People Successful?

高二英语阅读理解中等难度题查看答案及解析

Have you ever wondered why the roots of the plants always know which way to grow—into the soil but not above it? Some British scientists have recently solved this mystery.

It turns out that roots have special hairs that tie them into the soil and help them grow their way past obstacles, a team at the John Inners Center in Norwich reports in the February 29 issue of Journal Science.

“The key is in the fuzzy(有绒毛的)coat of hairs on the roots of plants,” says professor Liam Dolan. “We have found a growth control system that enables these hairs to find their way and to become longer when their path is clear.”

Root hairs explore the soil in much the same way a person would feel their way in the dark. If they come across an obstacle, they make their way around until they can continue growing in an opening. In the meantime, the plant is held in place as the hairs grip(紧紧抓住)the soil.

The hairs are guided by a clever chemical trick. A protein(蛋白质) at the tip of the root hairs called RHD2 helps them to take calcium(钙) from the soil. Calcium makes the hairs grow, and produce more RHD2, and take more calcium.

But when an obstacle blocks the hair’s path, or the hair reaches the surface of the soil, the cycle is broken and growth starts in another direction.

This system gives plants the flexibility to explore a complex environment and to live in even the most unpromising soils, says Dolan.

In poor soils such as in parts of Australia and Africa, native plants have adapted by producing enormous numbers of root hairs. A better understanding of this adaptation will allow scientists to develop hairy rooted crops that can grow in unfriendly environments.

According to Dolan, “Research in the John Inners Center is taking a breeding approach to increase hair length in wheat but it will be some time before new cultivars(栽培变种) are developed.”

1.The passage is mainly about _______.

2.How does the circle work?

3.We can infer from the last paragraph that ________.

高二英语阅读理解困难题查看答案及解析

Have you ever wondered what you’d do in a moment of danger and how you’d  36  to a terrorist on the plane or a guy wearing a mask and waving a gun while you’re standing  37  at the bank?

Stephanie Davies  38 .

The 21-year-old girl  39  such a moment last week in a  40  in Aurora, Colo., where she went to a late night showing of “The Dark Knight Rises” with her  41  , Allie. All of a sudden, a gas can flew by close to the two girls.  42  , Allie stood up and was shot in the  43  by a gunman. Stephanie saw Allie fell down in the aisle(过道), blood pouring out of her neck.  44  she moved on her knees to her friend, pulled her out of the aisle and pressed the wound with her fingers  45  the gunman moved around, firing into the  46  crowd. When the gunman again walked past the aisle, they played dead until he  47  .

Heroic? Well, clearly heroic.

“  48  Stephanie’s timely actions, I just talked with Allie, who is going to be fine,” said President Barack Obama after meeting the two girls in the hospital.

And Stephanie wasn’t the  49  hero in the theater that dark night in Aurora. Three young men---Jon,26, Matt,27 and Alex, 24---used their own  50  to protect their respective(各自的) girlfriends from the gunman’s bullets. Jon took a bullet for his girlfriend. The stories were  51  for Matt and Alex. The three men were among the 12 who didn’t come out of the theater alive.

“The  52  actions of these young Americans,” President Obama said, “represent what’s best in us, and they  53  us that out of this darkness a brighter day is going to come. I have the greatest  54  for people like Stephanie, Jon, Matt and Alex who don’t  55  to do what the situation demands, bringing heroic light to the darkest of dark nights.”

1.                A．refer          B．respond        C．adapt D．talk

2.                A．in turn         B．in silence        C．in time   D．in line

3.                A．knows          B．appears         C．wonders  D．imagines

4.                A．missed         B．faced          C．expected D．enjoyed

5.                A．street          B．restaurant       C．theater   D．stadium

6.                A．friend          B．sister           C．aunt D．cousin

7.                A．Tired           B．Annoyed        C．Frightened    D．Puzzled

8.                A．leg            B．wrist           C．arm  D．neck

9.                A．Madly          B．Suddenly        C．Secretly D．Hurriedly

10.               A．since          B．as             C．until  D．because

11.               A．waiting         B．chatting        C．staring    D．screaming

12.               A．passed         B．stopped        C．hid   D．escaped

13.               A．In spite of       B．Regardless of    C．Because of     D．In terms of

14.               A．typical         B．unique         C．usual D．only

15.               A．methods        B．bodies         C．tools  D．hands

16.               A．common        B．strange         C．similar D．different

17.               A．brave          B．immediate      C．generous  D．active

18.               A．warn          B．show          C．promise   D．inform

19.               A．hope          B．concern        C．pity  D．respect

20.               A．hesitate        B．regret          C．pretend   D．refuse

高二英语完型填空中等难度题查看答案及解析

I wonder why you won't do it as _____. It's the third time you have done so.

A.you told to B.be told C.tell you D.told to

高二英语单项填空困难题查看答案及解析

．

Have you ever wondered why different animals or pests have their particular colours? Colours in them seem to be used mainly to protect themselves．

Birds, especially seagulls, are very fond of locusts, but birds cannot easily catch locusts because locusts change their colours together with the change of the colour of crops．When crops are green, locusts look green．But when crops are ripe, locusts take on exactly the same brown colour as crops have．Some other pests with different colours from plants are usually easily found and eaten by their enemies．So they have to hide themselves in terror for lives and appear only at night．

If you study the animal life in any part of the world, you will find the main use of colouring is to protect themselves．Bears, wolves and other beasts move quietly through forests．They are usually invisible to the eyes of hunters, because they have the colour much like the barks of trees．

An even more strange act remains to be noticed．A kind of fish living in seas can send out a kind of very black liquid when it faces danger．While the liquid spreads over, its enemies cannot find it, and it immediately swims away．Thus, it has existed up to now though it is not powerful at all．

1.This passage mainly talks about ________．

A．the change of colour in locusts

B．the protective coloration of animals and pests

C．how a certain sea fish protects itself

D．animals or pests can dye themselves different colours

2.Locusts are ________ but they are not easily wiped out by their enemies because ________．

A．animals; they are powerful enough

B．beasts; they are dangerous to their enemies

C．pests; they take on the same colours as crops

D．birds; they fly extraordinarily fast

3.The pests that have different colours from plants usually appear at night because ________．

A．their enemies can easily find them and eat them

B．they have the habit of coming out in darkness

C．it’s easy for them to destroy plants in darkness

D．birds take their rest when night comes

4.Bears and wolves have the same colour as barks of trees because ________．

A．they fear other beasts

B．they like brown or grey colours

C．they enjoy walking through forests quietly

D．the colours help prevent themselves from being noticed

高二英语阅读理解中等难度题查看答案及解析

Have you ever wondered why birds sing? Maybe you thought that they were just happy. After all, you probably sing or whistle when you are happy.

Some scientists believe that birds do sing some of the time just because they are happy. However they sing most of the time for a very different reason. Their singing is actually a warning to other birds to stay out of their territory.

Do you know what a “territory” is? A territory is an area that an animal, usually the male, claims as its own. Only he and his family are welcome there. No other families of the same species are welcome. Your yard and house are your territory where only your family and friends are welcome. If a stranger should enter your territory and threaten you, you might shout. Probably this would be enough to frighten him away.

If so, you have actually scared the stranger away without having to fight him. A bird does the same thing. But he expects an outsider almost any time, especially at nesting（筑巢）season. So he is screaming all the time, whether he can see an outsider or not. This screaming is what we call a bird’s song, and it is usually enough to keep an outsider away.

Birds sing loudest in the spring when they are trying to attract a mate and warn others not to enter the territory of theirs.

You can see that birds have a language of their own. Most of it has to do with attracting mates and setting up territories.

1.Some scientists believe that most of the time bird’s singing is actually________.

A. an expression of happiness　 　　 B. a way of warning

C. an expression of anger　 　　　　 D. a way of greeting

2.What does the underlined word “territory”　 mean?

A. A place where families of other species are not accepted

B. A place where a bird may shout at the top of its voice

C. An area for which birds fight against each other

D. An area which a bird considers to be its own

3.Why do birds keep on singing at nesting season?

A. Because they want to invite more friends

B. Because their singing helps frighten outsiders away

C. Because they want to find outsiders around

D. Because their singing helps get rid of their fears

4.How does the writer explain bird’s singing?

A. By comparing birds with human beings

B. By reporting experiment results

C. By describing birds’ daily life

D. By telling a bird’s story

高二英语阅读理解中等难度题查看答案及解析