Searching for life on other planets

For more than thirty years scientists have been searching for signs of life on other planets. Most of these searches have been done over the radio. The hope is that someone in outer space may be trying to get in touch with us. Scientists also have sent radio and television messages, as well as messages on spaceships traveling through space, on the chance that someone may receive such messages.

Scientists are using powerful radio telescopes to “listen” to signals from about 1,000 stars, all within 100 light years of Earth. In addition, they will scan the entire sky to listen for radio messages from more distant stars. Using a computer, they will be able to monitor more than eight million channels at a time. Scientists are looking for any signal that stands out from the background noise.

Of the 200 billion stars in the Milky Way galaxy, scientists find that five percent are like our sun. Perhaps half of them have a planet like Earth. Such a planet would be a reasonable distance from the star for temperatures to be right for life. Based on the planets in our galaxy, most scientists agree that one or more of these planets may support some life.

However, many scientists wonder whether intelligent life exists on other planets. Some believe that thirty years of searching without any intelligible messages shows that no one is out there. They say that intelligence comparable to ours is unlikely.

Other scientists believe that our search hasn’t been long enough to rule out the possibility that intelligent life exists in our galaxy. Although our sun family is only about five billion years old, our galaxy is about 20 billion years old. In that time some scientists think it is likely that civilizations much more advanced than ours have developed. Perhaps these civilizations send us no signals; perhaps we have not recognized the signals they have sent us. If we hope to find intelligent life, these scientists believe that we have to keep looking.

To look for signals from distant stars, scientists _____.

A. have sent up spaceships to other planets

B. have sent radio and television messages to outer space

C. are listening to the radio messages all the year round

D. will use computers to pick up background noise

According to the passage, how many planets in our galaxy might be inhabitable?

A. 5 billion.    B. 10 billion.  C. 15 billion.  D. 200 billion.

Some scientists believe no other planet has life because ______.

   A. most of the researches have been done over the radio

   B. thirty years of searching doesn’t have any result

   C. we didn’t send messages on spaceships

   D. none of the other stars is right for life

Some scientists think there might be more advanced civilizations on other planets because _____.

A. some planets support more advanced civilizations

B. some civilizations have sent us signals we can’t recognize

C. the evolution of intelligence on other planets is unlike ours

D. some planets in our galaxy are much older than the earth

Which of these statements is true based on the information in the passage?

A. The earth is one of the oldest planets in our galaxy.

B. Most scientists believe that there is intelligent life on other planets.

C. Scientists are trying different ways to find signs of life on other planets.

D. More advanced civilization than ours have developed on other planets.

Searching the Internet may help middle-aged and older adults keep their memories sharp,US researchers said.
Researchers at the University of California, Los Angeles ,studied people doing web searches by recording their brain activity.
“What we saw was people who had Internet experience used more of their brain during the search,”Dr.Gary Small, a UCLA expert on aging, said,“This suggests that just searching on the Internet may train the brain and that it may keep it active and healthy.”
“This is the first time anyone has simulated(模拟)an Internet search task while scanning the brain,”Small said. His team studied 24 normal volunteers between the ages of 55 and 76. Half were experienced at searching the Internet and the other half had no web experience. However, the two groups were similar in age, gender and education.
Both groups were asked to do Internet searches and book reading tasks while their brain activity was monitored.
“We found that in the book reading task, the visual cortex— the part of the brain that controls reading and language — was activated,”Small said,“In doing the Internet search task, there was much greater activity, but only in the Internet-savvy（了解）group.”
He said it appears that people who are familiar with the Internet can engage in much deeper level of brain activity. Activities that keep the brain engaged can preserve brain health and thinking ability. Small thinks learning to do Internet searches may be one of those activities.
【小题1】Researchers          when volunteers were doing web searches.

Searching for airfares often seems like a game that passengers are bound to lose.

Prices change from day to day, even minute to minute. Looking through multiple websites for the best deal can be a big challenge. Even when you do book, there’s no guarantee that you are going to get the best price.

 “You just don’t know when to pull the trigger. It’s not like buying anything else I can think of,” said George Hobica, founder of Airfarewatchdog.com.

Harriet Levy paid $179 for a recent round-trip flight on American Airlines between New York and Fort Lauderdale, Florida. Sitting just one row behind her, Shirley Harrison paid $215. A few rows back, Ellis and Dianne Traub paid $317 each. There were at least 12 fares on the flight, ranging from $169 to $360.

There’s no reason for it, Harrison said.

Fares can vary significantly in just a few hours. One Delta flight from New York to Los Angeles jumped from $755 to $1,143 from a Friday to Saturday in late April, then fell to $718 on Sunday.

The flight was one of a dozen the Associated Press (美国联合通讯社)followed over three months for a vacation between July 16 and 22. The number one finding: avoid booking tickets on weekends. It’s the most expensive time to buy.

There’s no way to guarantee the best fare. But before booking, travelers should pay attention to this additional advice:

  ● Book on Tuesday, Wednesday and Thursday. That’s when airlines most often offer sales.

  ● Buy in advance, but not too early. The best time is four to six weeks before traveling. In general, prices for any given flight are highest eight to ten weeks and two to three weeks in advance.

  ● Make use of social media. Airlines are giving more benefits like exclusive (独家) sales to travelers who interact (互动) with them on Twitter and Facebook. Those specials are often gone within hours.

  ● The so-called discount airlines – JetBlue, Air-Tran, Southwest and Frontier – adjust their fares less frequently than other airlines, so you can feel more confident that the price will stay the same. But their prices aren’t always the lowest. Researching multiple airlines’ fares is the only way to get a good deal.

1. What can we infer from the first sentence of the text?

A. Passengers are unable to search for airfares.

B. Airlines often play games with passengers.

C. Airfares are set in different situations.

D. It’s difficult for passengers to get the best price.

2.The underlined phrase “pull the trigger” in Paragraph 3 probably means _______.   

A. start searching                                  B. get the highest price   

C. make a purchase                                        D. get on board the plane

3.By using a lot of figures, the author intends to _______.

A. show there is standard price for every single airline

B. discover the rules behind airfares

C. guarantee passengers a low price

D. prove airfares can vary widely

4.Passengers are advised to book flights _______.

A. in the middle of the week

B. on special websites

C. several months before traveling

D. with airlines which are famous for offering discount prices

Searching the Internet may help middle-aged and older adults keep their memories sharp,US researchers said.

Researchers at the University of California, Los Angeles ,studied people doing web searches by recording their brain activity.

“What we saw was people who had Internet experience used more of their brain during the search,”Dr.Gary Small, a UCLA expert on aging, said,“This suggests that just searching on the Internet may train the brain and that it may keep it active and healthy.”

“This is the first time anyone has simulated(模拟)an Internet search task while scanning the brain,”Small said. His team studied 24 normal volunteers between the ages of 55 and 76. Half were experienced at searching the Internet and the other half had no web experience. However, the two groups were similar in age, gender and education.

Both groups were asked to do Internet searches and book reading tasks while their brain activity was monitored.

“We found that in the book reading task, the visual cortex— the part of the brain that controls reading and language — was activated,”Small said,“In doing the Internet search task, there was much greater activity, but only in the Internet-savvy（了解）group.”

He said it appears that people who are familiar with the Internet can engage in much deeper level of brain activity. Activities that keep the brain engaged can preserve brain health and thinking ability. Small thinks learning to do Internet searches may be one of those activities.

1.Researchers          when volunteers were doing web searches.

A．studied the Internet

B．activated the brain

C．recorded their memories

D．monitored the brain activity

2.The two volunteer groups were         .

A．similar in education

B．of the same age

C．good at the computer

D．book lovers

3.According to the passage, we can learn that         .

A．reading books keeps the brain more engaged

B．searching the web keeps the brain more engaged

C．watching TV keeps the brain more engaged

D．chatting online keeps the brain more engaged

4.Which of the following is TRUE?

A．When you read, the whole brain will be activated.

B．Dr.Gary Small is a UCLA expert on brain health.

C．Internet searches can preserve brain health and thinking ability

D．People who read books may have a better memory.

Searching for airfares (飞机票价) often seems like a game that passengers are bound to lose.

Prices change from day to day, even minute to minute. Looking through multiple websites for the best deal can be a big challenge. Even when you do book, there’s no guarantee that you are going to get the best price.

“You just don’t know when to pull the trigger. It’s not like buying anything else I can think of,” said George Hobica, founder of Airfarewatchdog.com.

Harriet Levy paid $179 for a recent round-trip flight on American Airlines between New York and Fort Lauderdale, Florida. Sitting just one row behind her, Shirley Harrison paid $215. A few rows back, Ellis and Dianne Traub paid $317 each. There were at least 12 fares on the flight, ranging from $169 to $360.

There’s no reason for it, Harrison said.

Fares can fluctuate significantly in just a few hours. One Delta flight from New York to Los Angeles jumped from $755 to $1,143 from a Friday to Saturday in late April, then fell to $718 on Sunday.

The flight was one of a dozen the Associated Press followed over three months for a vacation between July 16 and 22. The number one finding: avoid booking tickets on weekends. It’s the most expensive time to buy.

There’s no way to guarantee the best fare. But before booking, travelers should pay attention to this additional advice:

? Book on Tuesday, Wednesday and Thursday. That’s when airlines most often offer sales.

? Buy in advance, but not too early. The best time is four to six weeks before traveling. In general, prices for any given flight are highest eight to 10 weeks and two to three weeks in advance.

? Make use of social media. Airlines are giving more benefits like exclusive (独家) sales to travelers who interact (互动) with them on Twitter and Facebook. Those specials are often gone within hours.

? The so-called discount (折扣) airlines – JetBlue, Air-Tran, Southwest and Frontier – adjust their fares less frequently than other airlines, so you can feel more confident that the price will stay the same. But their prices aren’t always the lowest. Researching multiple airlines’ fares is the only way to get a good deal.

1.What can we infer from the first sentence of the text?

2.The underlined phrase “pull the trigger” in Paragraph 3 probably means _______.

3.By using a lot of figures, the author intends to _______.

4.Passengers are advised to book flights _______.