【题目】Many science fiction stories tell about explorers arriving in a new world. The explorers then use some kind of high-tech device to test for breathable air or signs of life. But here on Earth, science fiction is becoming reality through a new sampling technology called environmental DNA, or e-DNA for short. Scientists can use it to identify rare or invasive species, study bio-diversity or estimate fish populations with just a little air or water.

Ryan Kelly is an ecologist at the School of Marine and Environmental Affairs at the University of Washington in Seattle. He works in a laboratory there with other researchers. They study the genetic material released by living creatures. “Essentially we can take a sample of soil or air and in our case water, and we can sequence(to arrange the order of genes)the DNA out of it and tell you what is there.

Ryan Kelly says he and his research team are studying water samples collected from Puget Sound. He says the cost of gene sequencing has “been reduced greatly in recent years.” That makes DNA testing more widely available.

Environmental DNA can be used in two ways. One is to identify the creatures that live in a certain place. The other is to confirm the presence or lack of a specific creature.

Caren Goldberg heads the new e-DNA lab at Washington State University in Pullman, Washington. She is one of the first biologists in the northwestern United States to take the technology from the testing phase to actually using it.

It is extremely useful for species that are really hard to find. I have spent many hours looking for species that I was pretty sure were there — looking under rocks, looking in water, doing all kinds of surveys.”

Caren Goldberg sees e-DNA as a way to get answers more efficiently, safely and with less destruction compared to traditional survey techniques. Until recently, scientists depended on diving deep, netting or using an electric current to temporarily catch fish.

We’re absolutely at this point where proof-of-concept has been established. I don't think everyone necessarily is ready for it yet, but I think the majority of people are.”

This newer way to identify what lives in the environment is becoming popular around the world. Animal experts in Vietnam are using the e-DNA to find the last, wild Yangtze giant softshell turtles. One researcher on the Caribbean island of Trinidad is using the sampling technology to find endangered golden tree-frogs. And in Madagascar, it is being used to identify amphibian diseases.

Ms. Goldberg has used e-DNA testing to confirm the local extinction, disappearance, of a leopard frog in the American state of Idaho. She has also been asked to document the spread of the New Zealand mud-snail in the state of Washington. The creature has been found in lakes and other waterways across the state.

Now, the U.S. Bureau of Land Management wants Caren Goldberg to look for the Columbia spotted frog in two other western states. The rare amphibian is a candidate for the federal government's threatened species list.

Scientists working with the technology say they do not expect robots to replace field biologists anytime soon. But the old-fashioned field work could soon be more targeted.

A related research goal is to show how long environmental DNA can last and how far it can travel in different environments.

【1】Paragraph One is intended as _____ of the passage.

A. the main idea

B. the introduction of the topic

C. a supporting detail of the main idea

D. a contrast of the main idea

【2】What has made E-DNA magic is that with E-DNA_____.

A. you are likely to find information about a species with a little air, water, or soil

B. some kind of high-tech device can be used to test for breathable air or signs of life

C. you are able to get answers more efficiently, safely though with more damage

D. the cost of gene sequencing has been reduced greatly in recent years.

【3】So far, the technique of E-DNA has NOT helped scientists search for ______.

A. wild Yangtze giant soft-shell turtles

B. endangered golden tree-frogs

C. the local extinction of a leopard frog

D. the spread of the New Zealand mud-snail

【4】Despites its advantage, we are still not sure of something about E-DNA. That is _____ .

A. the lasting time and the spreading area of E-DNA

B .the lasting time of E-DNA and too many species for E-DNA

C. too many candidates for E-DNA and the lasting time of E-DNA

D. robots and old-fashioned field work’s replacing E-DNA

【5】The passage can be sorted as a(n) _____.

A. science fictionB. experiment report

C. science reportD. bio-diversity discovery

【题目】Many families take their children on vacation. They will usually travel for a few days or weeks during school breaks. But Julie and Tim Rivenbark planned a longer vacation with their two childrenthe Rivenbark family is on a one-year trip around the world. They plan to visit 30 countries in all.

Right now, the four travellers are about halfway through their trip. Ms. Rivenbark says they are trying to see as much of the world as they can. She says “we have been through Europe, southern Africa, now we are kind of working our way through Asia. So we have been to a bunch of big cities, like Dubai, Johannesburg, Rome and Bangkok.”

The family has also spent time floating in kayaks(long narrow boats) in Italy, flying in hot air balloons in Myanmar, hiking to the Everest Base Camp in Nepal and going on a journey to see or hunt animals in South Africa.

Mr. Rivenbark says the family has also ridden on ostrich birds, elephants, and camels. But, he says, one of the most interesting experiences of the trip has been meeting new people.

People have been extremely friendly, very welcoming and love our kids—interacting with them and their reaction to see our kids enjoying themselves in their country.”

Eleven-year old Tyler says he has enjoyed learning about the people they have met. “I learned in Africa that people have very different lifestyles compared to Americans.” His sister, 9-year-old Kara, discovered that she liked Thai food.

Ms. Rivenbark says that the extended trip teaches the children a lot more than short visits would have. “I think that the longer we travel, the more impact it has on how they see the world. I can see them changing more than they can see themselves.”

It took the family a year to prepare for the trip. They had to sell their house and cars. Ms. Rivenbark quit her job and her husband is using unpaid leave. They carry small bags filled with lightweight clothing and whatever else they need. Ms. Rivenbark says she enjoys being able to carry everything she needs on her back. She says she does not miss the things she has back home. “What has become more important is making these memories as a family and taking those with us instead.” Tyler and Kara each have iPads so they can communicate with teachers to stay current with their schoolwork. Tyler is also creating a 365-day video blog.

The Rivenbarks will continue to head east for the next six months. They plan to visit Laos, Cambodia, Vietnam, China and Australia. To follow their adventures, visit their website: earthtrekkers.com.

【1】What makes the Rivenbarks different from other families is that _____.

A. they have their family trips during the children’s holidays

B. they have carefully planned their family trips for holidays

C. they plan to have a tour around the world without their children

D. they tour around the world with their kids not going to class

【2】During the travel, _____ impressed the kids as well as the parents most.

A. floating in kayaks in Italy

B. hiking to the Everest Base Camp in Nepal

C. interacting with different people

D. riding on elephants and camels

【3】The underlined word in Paragraph 7 extended is closest in meaning to _____.

A. expandedB. contented

C. shortenedD. intended

【4】We can infer from the passage that _____.

A. It will take the family one year to prepare and finish their travel

B. The kids are finishing their current study with the help of the Internet

C. The family are likely to stay in Asia for the second part of their trip

D. To afford such a trip around the world is really something easy for the family

【5】The passage is meant to _____.

A. share with the readers an extraordinary family trip

B. introduce some great parents and their jobs

C. remind us of the pleasure of getting close to nature

D. inform us of the benefits of travelling around the world

【题目】Are you looking for some new and exciting places to take your kids to? Try some of these places:

·Visit art museums. They offer a variety of activities to excite your kids' interest. Many offer workshops for making hand-made pieces, traveling exhibits, book signings (签名) by children's favorite writers, and even musical performances and other arts.

·Head to a natural history museum. This is where kids can discover the past from dinosaur models to rock collections and pictures of stars in the sky. Also, ask what kind of workshops and educational programs are prepared for kids and any special events that are coming up.

·Go to a Youtheater. Look for one in your area offering plays for child and family visitors. Pre-show play shops are conducted by area artists and educators where kids can discover the secret about performing arts. Puppet (木偶) making and stage make-up are just a couple of the special offerings you might find.

·Try hands-on science. Visit one of the many hands-on science museums around the country. These science play-lands are great fun for kids and grown-ups alike. They'll keep your child mentally and physically active the whole day through while pushing buttons, experimenting, and building. When everyone is tired, enjoy a fun family science show, commonly found in these museums.

【1】If a child is interested in the universe, he probably will visit _______.

A. a Youtheater

B. an art museum

C. a natural history museum

D. a hands-on science museum

2】What can kids do at a Youtheater?

A. Look at rock collections. B. See dinosaur models.

C. Watch puppet making. D. Give performances.

3What does "hands-on science" mean in the last paragraph?

A. Science games designed by kids.

B. Learning science by doing things.

C. A show of kids' science work.

D. Reading science books.

4Where does this text probably come from?

A. A science textbook. B. A tourist map.

C. A museum guide. D. A news report.

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