Many countries don't let people burn ___7___ for air in houses and factories in the city．Pollution by is now the most dangerous kind of air pollution. It is caused by heavy traffic. People say it's ___8____ to ride bikes. When you are riding, there is no pollution. But even in developed countries, most people don't go to work by bike.

A city without cars would be very strange, right? But Venice is such a city.

Venice is in the northeast of Italy. It wasn't built on land, like Beijing or Shanghai, but on more than 110 islands.  Seawater is everywhere around the city.

Even so, travel isn't difficult. The waterways have always been the best way to get around. There are 117 waterways and more than 400 bridges that can guide you where you want to go. People in Venice move from place to place by boat. They like to enjoy the scenery and cool summer nights while taking boat trips.  They can talk to other people as they go along.

Venice grew out of small islands in saltwater lakes when some Italians escaped from a war more than 1,500 years ago, and built homes there.

Water makes the city special, but it is also a big problem.

Once, people used too much underground water. This made the city get lower little by little. Now the city has gone down by 23 centimeters. Another problem is the rising seawater. The temperature has risen over the years.  This has made the ice of the Arctic Ocean (北冰洋) rnelt( 融化).

Every year, high waters hit the city in autumn and winter. When a lot of water comes, more than half of the city is underwater.

Scientists are trying different ways to stop the city from getting even lower.

46. According to the passage, which picture shows the right place of Venice?

47. Which is the most impossible way for people in Venice to get around in the passage?

A. On foot.        B. By boat.        C. By car.        D. By bike.

48. Why is Venice still getting lower and lower?

A. Because too many people live there.

B. Because the rising temperature has made the ice melt.

C. Because lots of bridges have been built.

D. Because the underground water is rising.

49. What seasons are dangerous for Venice because of high waters?

A. Summer and autumn.         B. Autumn and winter.

C. Summer and winter.          D. Spring and winter.

50. The passage is mainly about        .

A. the waterways of Venice      B. the history of Venice

C. the scenery of Venice         D. the problem of Venice

　　A city without cars would be very strange, right? But Venice is such a city.

　　Venice is in the northeast of Italy. It wasn't built on land, like Beijing or Shanghai, but on more than 110 islands. Seawater is everywhere around the city.

　　Even so, travel isn't that difficult. The waterways have always been the best way to get around. There are 117 waterways and more than 400 bridges that can lead you where you want to go.

　　People in Venice move from place to place by boat. They like to enjoy the scenery and cool summer nights while taking boat trips. They can talk to other people as they go along.

　　Venice grew out of small islands in saltwater lakes when some Italians escaped from a war more than 1,500 years ago, and built homes there.

　　Water makes the city special, but it is also a big problem.

　　Once, people used too much underground water. This made the city get lower, little by little. Now the city has gone down by 23 centimeters.

　　Another problem is the rising seawater. The temperature has risen over the years. This has made arctic (北冰洋的) ice melt (融化).

　　Every year, high waters hit the city in autumn and winter. When a lot of water comes, more than half of the city is under water.

　　Scientists are trying different ways to stop the city from getting even lower.

(1) According to the article, which picture shows the right position of Venice?

[　　]

(2) The best way to travel in Venice is by water, because ________.

[　　]

A．117 waterways can make your trip easy

B．you can talk to other people while you go along

C．you can enjoy the scenery and cool summer nights

D．it is not only easy but also you can enjoy yourself better

(3) There are ________ reasons that lead Venice lower and lower.

[　　]

(4) Which of the following statements (陈述) is TRUE?

[　　]

A．The first people coming to the island were Italians.

B．They came to Venice, because they liked the place very much.

C．They came here at the year 1 500.

D．The city has gone down to 23 centimetres.

(5) The article is mainly about ________.

[　　]

A．the position of Venice

B．the history of Venice

C．the problem of Venice

D．the scenery of Venice

BEING an astronaut sounds cool, doesn't it? In space, they get to do some pretty amazing things, like floating in zero gravity(重力).
However, there are also plenty of things that astronauts can't do because of their weightless environment, and that's very sad. What's worse, they can't even let their sadness show, because it's impossible to cry in zero gravity.
Of course, astronauts can still produce tears. But crying is much more difficult in space, according to The Atlantic(大西洋月刊) in January. Without gravity, tears don't flow(流动) down out of the eyes like they do here on Earth. This means that when you cry in space, your tears have nowhere to go-they just stick(粘) to your eyes.
In May 2011, astronaut Andrew Feustel experienced this during one of his spacewalks. "Tears," he said, "don't fall off of your eyes...They just kind of stay there."
Besides making your vision(视线)unclear, this can also cause physical pain. Back on Earth, tears are supposed to bring comfort to the eyes. But that's not the case in space. The space environment dries out astronauts' eyes, and when tears suddenly wet the eyes, it can cause pain rather than comfort. "My right eye is stinging(刺痛) like crazy," Feustel told his teammate during the walk.
Since gravity doesn't work in space, astronauts need some extra help to get rid of（除去） the tears. Feustel chose to rub his eyes against his helmet to wipe(擦) the tears away. Another choice is to just wait-"When the tears get big enough they simply break free of the eyes and float around," astronaut Ron Parise told The Atlantic.
There are lots of small things-things like crying-that we are so used to on Earth. We usually take them for granted until they become a problem in a totally different environment, like space.  There, astronauts can't talk to each other directly. They also can't eat or drink in normal ways. They can't even burp (打嗝), because there is no gravity to hold the food down in their stomach. If they do burp, they just end up throwing up（呕吐）everything in their stomach, according to the UK National Space Center.
Therefore, perhaps it's only space explorers who can honestly say: "Gravity, you're the best."
【小题1】From Paragraphs 2 and 3 , we can know that_______.