When my daughters reached the third and fourth grades, I sometimes allowed them to walk to and from school alone if the weather permitted. One warm spring day, a little dog followed them home after school. It had short legs and long lovely ears. It was the cutest dog I had ever seen and the girls begged me to keep it.

The dog was about twelve weeks old. It had no collar (项圈) or identifying marks of any sort. I didn’t know what to do. I thought about posting an advertisement but I really didn’t want to. It would break the kids’ hearts if someone should show up. Besides, its owners should have watched it more closely.

By the end of the week the dog was part of our family. It was very intelligent and good with the girls. The following week something told me to check the lost-and-found section in the local paper. One particular advertisement jumped out at me and my heart beat with fear for what I read. Someone was begging for the return of a lost dog in the neighborhood of our grade school. The owner sounded extremely eager. My hand shook, and I couldn’t bring myself to pick up the paper.

Instead, I pretended I hadn’t seen the advertisement. I quickly put paper away in the drawer and continued with my dusting. I never said a word about it to the kids or my husband.

By then we had named the dog. It was Kevin, so we called it Kevin. It followed the girls everywhere they went. When they went outside, it was one step behind them. When they did the housework, it was there to lend a hand.

There was only one problem with this seemingly perfect picture: my conscience (良心) was bothering me. I wondered in my heart whether I had to call that number in the paper and see if our Kevin was the dog they were desperately seeking. It was the most difficult thing for me to do.

But I had to make a decision.

The woman said, “Where is my dog? I would like to have a look at it.”

Chengdu has dozens of new millionaires, Asia’s biggest building, and fancy new hotels. But for tourists like me, pandas are its top     1    (attract).

So it was a great honour to be invited backstage at the not-for-profit Panda Base, where ticket money helps pay for research. I     2    (allow) to get up close to these cute animals at the 600-acre centre. From tomorrow, I will be their UK ambassador. The title will be     3    (official) given to me at a ceremony in London. But my connection with pandas goes back     4     my days on a TV show in the mid-1980s,     5     I was the first Western TV reporter     6    (permit) to film a special unit caring for pandas rescued from starvation in the wild. My ambassadorial duties will include     7    (introduce) British visitors to the 120-plus pandas at Chengdu and others at a research centre in the misty mountains of Bifengxia.

On my recent visit, I held a lively three-month-old twin that had been rejected by     8    (it) mother. The nursery team switches him every few     9    (day) with his sister so that while one is being bottle-fed,     10     other is with mum—she never suspects.

The giant panda     1     (love) by people throughout the world. Chinese scientists     2     (recent) had a chance to study a wild female panda with a newborn baby. She was a very     3    (care) mother. For 25days, she never left her baby, not even to find something     4     (eat)! She would not let any other pandas come near. She licked the baby constantly to keep it clean. Any smell might attract natural     5    (enemy) that would try to eat the little comforting panda. The mother held the baby in her front paws much the way a human does.     6     it cried, she rocked it back and forth and gave it little comforting pats. The mother continued to care for the young panda     7     more than two years. By that time, the panda no longer needed     8    (it) mother for food. However, it stayed with her and learned about the ways of the forest. Then, after two and a half years, the mother     9     (drive) the young panda away. It was time for her to have a new baby,     10     it was also time for the young panda to be independent.

Dora is a seven-year-old girl. One day, when she visited her friend Alice, she saw a beautiful bird in a cage on the balcony of the house. Alice told her it was her new pet. “How beautiful it is!” said Dora. “I also want to have such a bird as my pet.”

That day when Dora returned home, she told her mother about Alice’s bird. Then she asked, “Mom, can I also get a bird?” “Of course, you can,” said her mother. “But you need to wait because I’ve no time to visit a pet store these days.” Dora agreed. One day, when Dora was back home from school, she saw a cage in the living room. In the cage was a beautiful blue bird. Her mother was standing next to the cage, smiling. “Oh, a bird!” Dora shouted happily. She ran to it and looked at it happily. “It’s a birthday gift for you,” said her mother “Thank you, Mom. I love it so much!” said Dora excitedly.

The following day, Dora invited her friends to come over to see her bird. All of her friends said it was a really beautiful bird and Dora was very glad to hear that. She and her friends played with the bird for a long time that day. Her friends all wished they could have such a bird as their pet.

Sadly, a few weeks later, Dora became sick. The doctor told her parents that she got the flu and had to say at home. In order not to make her friends sick, her parents asked her friends not to come to play with her. Dora felt very sad. How she wished her friends would come and visit her! But she knew her parents were right. She’d better stay alone. Since Dora had no one to play with, she could only play with her bird. However, she felt that her bird didn’t seem to be happy either.

Dora watched her bird in silence.

When her mother came inside, Dora told her mother about her decision.

6 . Lithium (锂) is called “white gold” for good reason. The metal’s value has been growing sharply over the last several years, in a large part because it is an essential part of batteries as well as several key sustainable technologies where energy storage is of huge significance. As electric cars, wind and solar power have grown into major players in the energy industry, lithium has become key to engineering a future free of fossil (化石) fuels.

But acquiring lithium comes at an enormous cost. It often works like this: Water containing lithium is delivered to the surface from underground and mixed with fresh water. The mixture then sits in pools to get rid of water, leaving the rest of its contents behind as brightly colored “mud”. Then heat and chemical reactions are used to get lithium from that, changing it into powder which is then packaged and shipped to buyers around the world.

Any accident that releases mine contents into surrounding communities or the groundwater supply could have unimaginable long-term impacts. To be specific, indigenous (土著的) communities often bear the damage, and political leaders have typically given little weight to their concerns. In Arizona, for example, an expanding lithium mine is threatening the Hualapai Tribe’s cultural and historic sites. Recently, mining lithium and other precious metals has brought about conflict: How do you ensure the availability of materials essential to the future of renewables while protecting those communities’ rights?

Mining of the metal is expected to increase dramatically in coming years. Over time, experts say, that will reduce greenhouse gas emissions (排放) by making electric cars more affordable and, therefore, more popular. As environmentally conscious consumers buy electric cars in ever-greater numbers, it’s important to be aware of the dirty process that powers those clean air vehicles.

2. 只允许修改10处，多者（从第11处起）不计分。

China and Western country may have different cultural beliefs about certain animals. But when it comes to pigs, we somehow reach an agreement that pigs are lazy, ugly, stupidly and shameless. Neither of these words describing pigs are exactly positive. Moreover, the truth is what pigs have some good qualities. And there’s probably no good time to clear their names than now, with the arrival of the Year of the Pig on Chinese Spring Festival, which fell February 5 this year. According to a paper publishing in 2017, pigs can tell between those who treat them well or those who don’t. Perhaps these are the qualities of pigs to keep it in mind—their intelligence, cuteness and patience.

Plastic is a huge problem for our planet. It is really     1     (challenge) to get rid of and a lot of it ends up in nature or in the ocean in particular. There, it is a threat     2     our animals and plants.

Now a company from the Netherlands, a small country in western Europe, says that it will use plastic     3     (find) in the ocean to build roads. Volker Wessels     4     (turn) the plastic into building blocks for the roads. They will be like puzzle pieces     5     fit into each other.

Not only will this be good for the environment, but also it will be good for the people who look after roads. If a part of the road     6     (damage), it will be easy to remove it and replace it with another piece. The company says that nearly any type of plastic can be used     7     (make) the road pieces.

Scientists     8     (work) on the project say that they are in the final stages of testing the materials for     9     (safe). They say that the first road built will be     10     bicycle path somewhere in the Netherlands.