When a leafy plant is under attack, it doesn’t sit quietly. Back in 1983, two scientists, Jack Schultz and Ian Baldwin, reported that young maple trees getting bitten by insects send out a special smell that neighboring plants can get. These chemicals come from the injured parts of the plant and seem to be a warning. What the plants pump through the air is a mixture of chemicals known as volatile organic compounds(VOCs).

Scientists have found that all kinds of plants give out VOCs when being attacked. It’s a plant’s way of crying out. But is anyone listening? Obviously. Because we can watch the neighbors’ react.

Some plants pump out smelly chemicals to keep insects away. But others do double duty. They pump out perfumes to attract different insects who are their natural enemies. Once the insects arrive, the tables are turned. The attacker who was lunching now becomes lunch.

In study after study, it appears that these chemical conversations help the neighbors. The damage is usually more serious on the first plant, but the neighbors stay safer because they heard the warning and knew what to do.

Does this mean that plants talk to each other? Scientists don’t know. Maybe the first plant just made a cry of pain or was sending a message to its own branches, and so, in fact, was talking to itself. Perhaps the neighbors just happened to hear the cry by accident and so wrong information was exchanged.

Charles Darwin, over 150 years ago, imagined a world far busier, noisier and more intimate than the world we can see and hear, our senses are weak. There’s a whole lot going on.

1.What does a plant do when it is under attack?

A.It makes noises. B.It gets help from other plants.

C.It stands quietly. D.It sends out certain chemicals.

2.What does “the tables are turned” mean in Paragraph 3?

A.The attackers are attacked. B.The insects gather under the table.

C.The plants get ready to fight back. D.The perfumes attract natural enemies.

3.Scientists find from their studies that plants can__________.

A.talk to one another B.predict natural disasters

C.protect themselves against insects D.help their neighbors when necessary

4.What can we learn from the last paragraph?

A.The world is changing faster than ever. B.People have stronger senses than before.

C.The world is more colorful than it seems. D.People in Darwin’s time were full of imagination.

Have you ever heard of “a ball of energy”? People often use it to describe very active children. But today we tell about an invention called the socket, that is a real soccer ball of energy. Julia Silverman explains that in fact the socket is a portable generator.

Julia Silverman and Jessica Matthews developed the socket as part of a group project for an engineering class at Harvard University. There are mechanisms in a socket. When you kick, hit or throw it, energy is then kept in it by these mechanisms instead of disappearing into the environment.

Then the user can put something directly into the ball, like a lamp, or a mobile phone charger so that they can get energy from it. For every fifteen minutes of the game play, the socket can provide enough electricity for an LED lamp for three hours, and the ball can store up to 24 hours’ electricity.

The International Energy Association reported last year that nearly one and a half billion people in the world had no electricity to use, and most of them live in sub-Saharan Africa and in India and other countries in Asia.

Julia Silverman and Jessica Matthews both had experiences in developing countries before they began the project. They knew that power shortages are a serious problem in really areas. There’s an energy crisis in the world. One out of every five people in the world don't have any electricity, there are a lot of health problems because what people use instead of any electricity are harmful choices like kerosene lamps, which produce a lot of smoke.

Julia Silverman says the socket ball is one small solution to a big problem. Jessica Matthews and Julia Silverman hope their socket ball will shine more light on the problem of power shortages. It offers people a chance to put their energy into the world’s most popular sport and get some energy in return.

1.From the passage, we know the socket is__________.

A.an active child B.an invention C.a lamp D.a mobile phone

2.The underlined word “crisis” in the passage means a time of__________.

A.difficulty B.safety C.success D.sadness

3.We can infer from the passage that__________.

A.active children care more about playing socket

B.people are expected to get some energy by playing socket

C.Julia Silverman has never been to developing countries before

D.kicking a socket can let the energy disappear into the environment

4.The best title for the passage should be__________.

A.A soccer ball that gives energy B.The way to help save electricity

C.The best way to solve energy problems D.An invention changing the world

You can buy a box of Crayola crayons in 152 colors today, but way back in 1903, they only came in eight colors. And that box of Crayola crayons was a huge improvement over the first crayons, which only came in black.

Wax crayons were mostly used for industrial purposes until cousins Edwin Binney and Harold Smith introduced their brightly colored crayons for kids. Edwin’s wife made up the name Crayola by putting “craie”(French for chalk)together with“ oleaginous”(which means oily). In other words, oily chalk!

It’s hard to understand just how modern crayons are different from those in the past without look at the history of the crayon. In 1864 Edwin’s dad, Joseph Binney, started a chemical factory in New York City. It made a black pigment by burning oil. When the two cousins took over the factory in 1885, they started making a number of industrial art products for home and school use, but from 1900 to 1902, they started making pencils and dustless chalk for school blackboards in American classrooms. Soon after that, colored crayons were made. But the crayons they first made were not safe for kids, so they developed crayons that would be safe. The first box they sold-the one with eight colors--cost just five cents.

To celebrate the hundredth birthday of Crayola crayons in 2003, a special 100-color box was created, adding four new colors to the existing 96-color box. Over the years, as the company grown, it has introduced more than 400 different colors. Today there are over a hundred types of Crayola Crayons. They are available in boxes printed in 11 languages including Swedish, Spanish, Portuguese, Norwegian, Italian, German, French, Finnish, English, Dutch and Danish. Two billion Crayola Crayons are produced yearly. Also you can find crayons that smell good, crayons that wash out of clothes, and even egg-shaped crayons. Nowadays, plenty of other companies make colored crayons for children, too.

1.What color were the first crayons?

A.Black B.Red C.Yellow D.Green

2.The first eight-color Crayola crayons started to be sold in the year__________.

A.1864 B.1885 C.1903 D.2003

3.Which of the following statements are TRUE about Crayola crayons?

A.The name Crayola was a mixture of two English words.

B.The first Crayola crayons were not safe but very expensive.

C.The company invented four more colors for its 100th birthday.

D.Today Crayola crayon boxes are now also printed in Chinese language.

4.What’s the passage mainly about?

A.The changes of the colors of Crayola crayons.

B.The history of the invention of Crayola crayons.

C.The two cousins who made Crayola crayons.

D.The reason why Crayola crayons are still popular.

下面文章中有五处需要添加小标题。请从以下选项(A、B、C、D、E和F)中选出符合各段意思的小标题。选项中有一项是多余项。

A. Places to Stay B. Places to Visit C. Weather

D. Shopping E. History F. Restaurants

Savannah City Guide

1.

If you want to spend the night in Savannah, you have lots of place to choose from. You can stay at a big hotel a small inn, or a comfortable motel. Savannah's hotels, motels and inns are famous for their friendly service. Call one of these places to make your reservation.

2.

Savannah is well known for its wonderful restaurants Many restaurant serve local, seafood or old-fashioned Southern food. The following are sonic of the best restaurants in the area.

3.

If you like to shop, Savannah is the place for you! You'll find all kind of stores in Savannah. You can go shopping in small stores or big shopping malls. Are you looking for a special treasure or a great deal? You'll find it in Savannah.

4.

There are so many things to do and see in Savannah. The sightseeing is great. You can visit beautiful historic homes and museums. You can take a boat tour or visit Civil War forts. With all of Savannah's history, art, and beautiful buildings, be sure to take the time to enjoy all that Savannah has to offer!

5.

Savannah has lots of sunshine throughout the year. Summer are hot and humid. Winters are generally mild. Temperatures usually range between 30 degrees Fahrenheit (-1 degree Centigrade) and 90 degrees Fahrenheit (33 degrees Centigrade).

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