Millions of years ago, horses had many toes(脚趾). They had four toes on each front foot and three toes on each back foot. The horses were no bigger than cats.
These small horses lived in the forest. Their toes helped them run over the soft, wet ground. It was very hot in the forest. But the weather gradually(逐渐地) changed. It became colder and colder, many trees could not live in cold weather. They died and fell, and open fields took the place of forests, the sun made the ground dry and hard.
Horses began to change, too. They began to get bigger. This took a long, long time, on the dry and hard land. Horses needed only their middle toe for running. Their middle toes became hard. After a long while, horses had only one hard toe on the foot.
1. Millions of years ago, the horse had four toes on each of its ________.
| A．left feet | B．right feet | C．back feet | D．front feet |
| A．Because the ground was dry and hard. |
| B．Because the weather became colder and colder. |
| C．Because it was very hot. |
| D．Because the horse lived in it. |
| A．the weather never changed |
| B．cats were once much bigger than horses |
| C．animals have always been the same as they are today |
| D．horses have changed a lot in the past millions of years |
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【推荐1】Are you afraid of going to the dentist(牙医)? If so, you're not alone.
These fears could just be in our heads, however. According to a recent survey by Martin Tickle, a professor at Manchester University in the UK, the pain isn’t felt most of the time in dental surgeries(牙科手术). In fact. among the 451 interviewed patients，75％ reported no pain at all during their visits, including situations when they had their teeth pulled out.
Could it be the sound of the drill(钻头)then?
“I found that the sound of drilling can evoke deep worry in dental patients. Actually they don’t have any pain. " Hiroyuki Karibe, a scientist at Nippon Dental University in Tokyo, told the Guardian.
To find the reason why a drill might bring on a racing heart, Karibe divided the volunteers into low-fear and high-fear groups based on how much they feared a trip to the dentist. Volunteers were played the sound of a drill while their brain activities were watched by a machine.
What Karibe found in the low-fear group was increased activity in the areas of the brain relative to auditory processing(听觉处理)， which means， for these people， the sound of dental drills is no different from other sounds
In the high-fear group, however, the brain area that was activated(激活)was different. It was the area that carries out a number of duties, including learning, feelings and, most importantly, memory. This means that these volunteers not only heard the sound, but they remembered it-they made connections between the sound of a drill and the worry it produced in the past, causing their worry to return.
Understanding how brains reply to the sounds of dentists ' drills could help scientists find ways to make patients more relaxed, according to Karibe, because patients who worry about going to the dentist might keep putting off their visits. But the best way is to keep your teeth healthy.
1. How does the writer explain that the pain isn’t felt most of the time in dental surgeries?| A．By showing facts with numbers. | B．By asking questions one by one. |
| C． By giving examples group by group. | D．By comparing results of patients. |
| A．减轻 | B．引起 | C．显示 | D．阻止 |
| A．It produced some worry in the volunteers in the low-fear group |
| B．For the low-fear group, it activated the brain area dealing with learning, feelings and memory |
| C．For the high-fear group, it caused more activities in the brain area relative to auditory processing. |
| D．It made people in the high-fear group remember their past uncomfortable memories. |
| A．How the study might be useful. |
| B．Some new ways to treat teeth |
| C．The proper way to treat dental patients. |
| D．The importance of keeping our teeth healthy. |
| A．To show us different areas of fear in brains. |
| B．To introduce us a recent survey by a scientist. |
| C．To help us have less fear of a trip to the dentist. |
| D．To make it clear that the sound of drilling is not terrible. |
【推荐2】When I was young, I lived in Scotland with my parents. I had a good time there. One morning, I ran to the garden, and said to the old gardener. “Today I am going up the mountain.”
“No, no, Missey, not today,” he said, “It will rain.”
“No, it will not rain.” I said. “The sun is up.”
“I don’t care for the sun. The pimpernel (海绿) says it will rain, so it will. Flowers always tell the truth. When they say rain, go and get your umbrella.” said the old man.
Sure enough, by noon the rain was pouring (倾倒) down. After that, I looked with great respect (崇敬) at the flower. But the pimpernel is not the only plant that is a “weather prophet”(预言者).
If you find the African marigolds (金盏花) shut (合上) after seven o’clock in the morning, you may be pretty sure that there will be a rainy day. Most “weather prophet” plants shut up for rain. Tulips (郁金香) are careful not to open their cups very wide in the morning if it is probably going to rain. The cause of the opening and closing may be the difference in light. Perhaps these plants shut their flowers because of the short of light.
But some plants open for rain. The verbenas (马鞭草) are one kind of them. They love the shade and become smaller in a strong light. The roses make no changes. The light seems to make no difference to them.
On the whole, if you go into your garden, and find tulips, marigolds shut, you’d better not go for picnics or long walks.
1. Why did the old gardener think it would rain?| A．The sun told him. | B．The cloud told him. |
| C．The weather report told him. | D．The pimpernel told him. |
| A．They love shade. | B．They tell about the weather. |
| C．They open for rain and light. | D．They become smaller in a strong light. |
| A．When the verbenas do not shut. | B．When the roses shut in the sunshine. |
| C．When the tulips open wide in the daytime. | D．When the African marigolds shut after 7:00 am. |
【推荐3】“The delivery(递送) driver has your food and is on his way.” This is a message you might receive after placing a takeout order. But in the near future, a self-driving car may bring food to your door instead of a human driver. Baidu and Meituan are now working together to use self-driving technology to deliver food. They will be experimenting with this in the Xiongan New Area, Beijing Evening News reported.
The self-driving cars will mainly be used to send group orders, as opposed to the single orders that are usually handled by delivery drivers. For example, if a company orders food for its staff, a self-driving car will bring the entire order to the company. Sina Tech noted that using self-driving cars will be a revolution (革命) in the food delivery industry, as it will eliminate (消除) the cost of labor (劳动力).
Online food delivery services have developed rapidly in China. Almost 300 million users have used online services to order food, the Xinhua News Agency reported. In 2016, Meituan Waimai ranked highest among all food delivery companies according to total orders, with Chinese food delivery company Ele.me ranking second.
Self-driving delivery services will promote (促进) the development of the industry. But that doesn’t mean that delivery drivers will lose their jobs. There are still some problems to work out, according to internet startup service provider 36kr. For example, self-driving cars can drive smoothly on cement roads, but have problems driving on dirt roads. There are other safety-related problems that must also be solved before self-driving cars can be used .
1. _____ are working together on self-driving delivery services.| A．Baidu and Meituan | B．Baidu and Ele.me |
| C．Meituan and Sina Tech | D．Meituan and Ele.me |
| A．Because it uses cars instead of motorbikes or e-bikes. |
| B．Because it can better deal with large orders. |
| C．Because it costs less than hiring delivery drivers. |
| D．Because it can attract more customers. |
| A．Ele.me | B．Baidu | C．Sina | D．Meituan Waimai |
| A．They will mainly be used to handle single orders. |
| B．They will be tested in the Xiongan New Area. |
| C．They will cost customers less money. |
| D．They are safer than human delivery drivers. |
| A．No one will deliver your takeout food in the future. |
| B．There are still problems with self-driving cars. |
| C．Food delivery services are developing rapidly in China. |
| D．Self-driving cars will be used to deliver food. |
In July, China introduced the “double reduction (双减)” policy. It hopes to reduce schoolwork burden(负担) on primary and junior high school students. The policy calls for reducing homework and after-school classes. According to the policy, children below the third grade will not have homework any more. It should take no more than 90 minutes for junior high school students to finish their homework. After-school training institutions (校外培训机构) are not allowed to offer extra education courses or advanced (超前的) teaching on weekends, holidays or during winter and summer vacations. One month has passed since the new semester began. How do students feel about this new policy?
“Our homework is clearly less than before,” said 13-year-old Shen Yuzhe from Beijing. “We are not encouraged to buy workbooks any more. The exercises are mainly from the textbook.”
According to Shen, students have enough time to process new knowledge now.
“Our teachers are also giving us more chances to do experiments and learn from real life,” said Shen. “For example, we went to research earthworms(蚯蚓) in a field during a biology class. This is a much better way to learn things than just hitting the books.”
For 13-year-old Zhang Hangming from Tianjin, the best thing about “double reduction” is the increased time in after-school activities. “We can now spend more time taking part in clubs and activities, such as dancing, volleyball and drama. I have joined a group called “leadership development” where I can learn all kinds of skills beyond schoolwork,” said Zhang.
Both Shen and Zhang find there are fewer exams now. But they think it’s not necessarily a good thing. “Exams push me to study harder. Each exam shows my progress as well as my weak points,” Zhang said.
Shen also pointed out that when burden is lightened, self-discipline(自律) becomes the key. “Some students now spend more time having fun when homework is finished early. But if you use all the free time to relax, you might fall behind other students,” he said.
1. The “double reduction(双减)” policy aims to ________.| A．make vacations longer for students | B．reduce the pressure put on teachers |
| C．reduce students’ schoolwork burden | D．help students become more competitive |
| A．Homework is not allowed for primary students. |
| B．Junior high schools should reduce their homework. |
| C．All after-school training institutions are asked to close. |
| D．After-school training institutions should offer advanced teaching. |
| A．Sports. | B．Math. | C．Public speaking. | D．Computer programming. |
| A．Students should learn to be self-discipline. |
| B．Students should use all the free time to relax. |
| C．Exams aren’t necessary because they only show students’ weak points. |
| D．Students should spend more time having fun after finishing homework. |
【推荐2】Tigers are strong and dangerous animals. But now they are in danger.
There were eight kinds of wild (野生的) tigers in the world before.But during the 20th century, only five were left. The number of wild Siberian tigers (东北虎) was about 300, but now it is about 22. They’re in danger of dying out. If we does nothing, we won’t be able to see them after ten to twenty years.
To stop people from killing tigers, and to make tigers more, the World Wildlife Fund (世界自然基金会) started to protect wild tigers. China and another twelve countries joined it.
However, it’s not enough. Remember that nature is a food chain (食物链). If we hurt and kill too many cows and pigs, tigers will die out because of hunger (饥饿). So the most important thing is to save the animals that tigers eat. To protect the wild tigers, we need to call on (号召) more people to stop eating and killing wild animals.
1. During the 20th century, ________ kinds of wild tigers were left.| A．three | B．five | C．eight | D．twenty |
| A．5% | B．7% | C．93% | D．30% |
| A．trees | B．grass | C．people | D．cows and pigs |
| A．There are about 22 wild Siberian tigers now. |
| B．There are twelve countries in the World Wildlife Fund. |
| C．Wild tigers feed on pigs and cows. |
| D．We need to protect the wild tigers. |
| A．why and how we protect the wild tigers |
| B．people does everything they could to protect the wild tigers |
| C．the wild tigers will die out after ten to twenty years |
| D．the most important thing is to save the animals that tigers eat |
When you think about a Hawaiian holiday, you probably think about relaxing on the beach with a drink in your hand and the sun on your body. Although Hawaii is certainly a perfect place for a lazy holiday, there is much more than just sunshine and beaches.
These large islands of Hawaii each offer something a little different, so where you go will depend on what kind of holiday you prefer.
Molokai (莫洛凯岛)
If you go on holiday to experience local culture and history, then there is no place better than the island of Molokai. Take a tour of the Halawa Valley and find out what Hawaii might have looked like hundreds of years ago.
Kauai (考艾岛)
Do you prefer your holiday to be more exiting? The island of Kauai is home to the Napali Coast State Wilderness Park, a state park full of beautiful scenery and nature trails (小路). Why not try a hike along the ocean on the 18-kilometer trail?
The Island of Hawaii
Hawaii’s biggest city Honolulu (火奴鲁鲁) is on the island of Oahu, but Oahu isn’t the state’s largest island. That would be the Island of Hawaii, also called the “Big Island”. And if you dream about leaving the city behind and spending all of your time with the local wildlife, this may be the place for you! Here you can swim with manta rays (魔鬼鱼) and maybe you’ll see a dolphin or a humpback whale by the Kona Coast.
1. In which island can you experience local culture and history?
| A．The Island of Kauai. | B．The Island of Hawaii. | C．The Island of Molokai. |
| A．Its biggest city is Oahu. |
| B．It is the largest island of the state. |
| C．We can swim with a humpback whale there. |
| A．Three large islands of Hawaii. |
| B．A state park full of beautiful scenery. |
| C．Home to the Napali Coast State Wilderness Park. |
