Since English biologist Charles Darwin published On the Origin of Species in 1859, scientists have vastly improved their knowledge of natural history. However, a lot of information is still of the speculation, and scientists can still only make educated guesses at certain things.
One subject that they guess about is why some 400 million years ago, animals in the sea developed limbs (肢) that allowed them to move onto and live on land.
Recently, an idea that occurred to the US paleontologist (古生物学家) Alfred Romer a century ago became a hot topic once again.
Romer thought that tidal (潮汐的) pools might have led to fish gaining limbs. Sea animals would have been forced into these pools by strong tides. Then, they would have been made either to adapt to their new environment close to land or die. The fittest among them grew to accomplish the transition (过渡) from sea to land.
Romer called these earliest four-footed animals “tetrapods”. Science has always thought that this was a credible theory, but only recently has there been strong enough evidence to support it.
Hannah Byrne is an oceanographer (海洋学家) at Uppsala University in Sweden. She announced at the 2018 Ocean Sciences Meeting in Oregon, US, that by using computer software, her team had managed to link Homer’s theory to places where fossil deposits (沉积物) of the earliest tetrapods were found.
According to the magazine Science, in 2014, Steven Balbus, a scientist at the University of Oxford in the UK, calculated that 400 million years ago, when the move from land to sea was achieved, tides were stronger than they are today. This is because the planet was 10 percent closer to the moon than it is now.
The creatures stranded in the pools would have been under the pressure of “survival of the fittest”, explained Mattias Green, an ocean scientist at the UK’s University of Bangor. As he told Science, “After a few days in these pools, you become food or you run out of food... the fish that had large limbs had an advantage because they could flip (翻转) themselves back in the water.”
As is often the case, however, there are others who find the theory less convincing. Cambridge University’s paleontologist Jennifer Clark, speaking to Nature magazine, seemed unconvinced. “It’s only one of many ideas for the origin of land-based tetrapods, any or all of which may have been a part of the answer,” she said.
1.Who first proposed the theory that fish might have gained limbs because of tidal pools?
A. Hannah Byrne. B. Charles Darwin. C. Steven Balbus. D. Alfred Romer.
2.Why were tides stronger 400 million years ago than they are today according to Steven Balbus?
A. There were larger oceans. B. Earth was under greater pressure.
C. Earth was closer to the moon. D. The moon gave off more energy.
3.The underlined word “stranded” in Paragraph 8 probably means “________”.
A. settled B. trapped C. abandoned D. found
4.What is the focus of the article?
A. The arguments over a scientific theory.
B. The proposal of a new scientific theory.
C. Some new evidence to support a previous theory.
D. A new discovery that questions a previous theory.
Last week I was riding my special motorbike and then stopped at a convenience store. As I was getting my wheelchair off the back, a man watched me from his car and I noticed a wheelchair in his back seat. We spoke for a moment and I asked him about the wheelchair. He answered that it was for his daughter. “Well, do you think she would like to go for a ride on my motorbike with me?” I asked. He seemed shocked that a total stranger would ask him this. He thought about it for a second and said, “OK, as long as I can follow you.”
He introduced me to Amy and he sat her on my back seat. Her father followed me for a few miles and she talked non-stop about what she wanted for Christmas. As we came back to the convenience store, she said, “This ride is the best Christmas present I could ever receive. I have been in a wheelchair my whole life and didn't know I could do this.” I told her about some of the other things I do (ski, travel the world by myself, etc.). As her father was taking her off my bike, she turned to him and said, “Oh Daddy, I'm going to be OK. Mr. Bryant does all kinds of things, and I will too.” Her father turned away as a tear of joy rolled down his cheek. He hugged me and said, “I was sitting here praying for a gift for Amy that would encourage her. She often felt that her life was dull compared to other children. God answered my prayer just now. Now I pray that God will bless you for your gift to Amy today.” I believed what he said. Being kind and thoughtful to others, we can be an answer to prayer.
1.How did the father feel at first when the author invited his daughter for a ride?
A. He felt surprised because he didn’t know the author.
B. He was moved because the author offered to help his daughter.
C. He was happy because his daughter could gain excitement.
D. He felt nervous because he was worried about his daughter's safety.
2.According to the passage, the girl ____________.
A. was satisfied with her life
B. used to be a completely healthy person
C. was inspired by the author's experiences
D. was unwilling to communicate with a stranger
3.What was the author's gift to Amy according to the girl's father?
A. The motorbike. B. The wheelchair. C. The blessing. D. The ride.
4.What can we infer from the passage?
A. The author usually drove too fast.
B. The author was a man with disability.
C. The author worked in a convenience store.
D. The author often offered strangers a ride on his motorbike.
Have you ever had one of those days when all you wanted to do was read an emotionally powerful story that would cause you to tears? Most of us tend to be attracted by stories that reach us on multiple levels, including sadness. There are plenty of books that make you cry (and sometimes laugh) and that you can really sink your teeth into. Here are four of them.
1. The Kite Runner
This realistic and moving description of life in Afghanistan accounts for the people who were badly affected by the Taliban. You’ll cry as you get to know the familial relationships and cruelty involved, but you’ll also get a sense of hope as you quickly read through this appealing novel.
2. The Book Thief
Let’s put it this way: Death itself is the narrator. The story is about a young girl named Liesel who has to live with foster parents during World War II. On the way to her new home, her brother dies, setting the gloomy tone for the story. There is hope, however, when Liesel discovers her love for reading and makes a relationship with a young Jewish man she helps hide from the Nazis.
3. The Fault in Our Stars
This is probably the most likely book on the list to make you cry, as it records the experiences of teens who are dying from cancer and living their last days in love. Their lifestyle is tragic and disturbing at the same time, as we watch their health worsen. The real tragedy is the love story between the main characters, who know that their romance is fruitless.
4. A Child Called “It”
Easily one of the saddest stories of abuse in recent decades, A Child Called It is based on the true story of Dave Pelzer, a boy from California who suffered at the hands of his cruel family. The tears will come from both sadness and the inspiration tied to Dave’s fight for survival in an environment where he is believed worthless.
1.What do the four books have in common?
A. They are all about cruel wars. B. They are all adapted from true stories.
C. They are all about suffering children. D. They all probably make you cry.
2.Which book is about a young victim whose family treated him cruelly ?
A. The Kite Runner. B. The Fault in Our Stars.
C. A Child Called “It”. D. The Book Thief.
3.The passage is intended to __________.
A. introduce some moving books B. inspire us to read more
C. explain why we love reading D. advise us to buy some books
听下面一段独白，回答以下小题。
1.What is the most important requirement for this job?
A. Experience. B. Creativity. C. Energy.
2.What do children do in the morning?
A. Go hiking. B. Write short essays. C. Report to the leaders.
3.When is the application due?
A. In late April. B. In mid-May. C. In early July.
听下面一段较长对话，回答以下小题。
1.Who will know about the move tonight?
A. Lily. B. Katie. C. Jason.
2.According to the woman, what is much better in France?
A. The food. B. The weather. C. The schools.
3.What does the man hope to do about his family?
A. Bring them to France. B. Leave them in America. C. Visit them in a few months.
4.What is the relationship between the speakers?
A. Boss and secretary. B. Family members. C. Co-workers.
听下面一段较长对话，回答以下小题。
1.In the beginning, what does the woman think George is doing?
A. Reading. B. Coloring. C. Writing.
2.Why are some of the texts marked in green?
A. They are the main ideas. B. They are important details. C. They are a bit more difficult.
3.According to George, why is active reading useful?
A. It helps students learn new words.
B. It shows students what they already know.
C. It’s a good learning method for both slow and fast students.
