The United States has more tornadoes (龙卷风) than any other country in the world. In normal year there are 800 to 1, 000 tornadoes. Most happen in the middle part of the country. Tornadoes form when warm and cool air meet. In the Midwest, the warm air from the Gulf of Mexico often meets the cold air from Canada.
The usual tornado season is March through May. Tornadoes form most often in the afternoon and early evening. There is often no warning of tornado. People who live in the Midwest know the signs (征兆) of tornado activity. The sky becomes dark, often a greenish color. Dark clouds appear in the sky and there is often large hail (冰雹) . Suddenly, there is loud sound, like train or jet plane. Sometimes, two, three, five, ten or more tornadoes can form over a large area.
This type of tornado activity hit Oklahoma and Kansas in May 1999. The day was stormy, with heavy thunderstorms in the afternoon. As the storms continued, tornadoes began to form. Dozens of tornadoes hit towns and neighborhoods in Oklahoma then in Kansas. Some stayed on the ground for several hours, destroying everything they touched. The tornadoes killed 43 people and injured 600 others. They destroyed thousands of homes and businesses. In some areas, not one home stood. In other areas, the tornadoes destroyed every home on the left side of the street, but didn't touch any homes on the right side. The tornadoes lifted people and cars into the air and then threw them back down to earth. So it is important to know where to hide and how to protect yourself in the face of a tornado.
1. What can we learn about tornadoes in America?| A．They may appear in groups. |
| B．They usually happen in the summer. |
| C．There are more tornadoes in the Eastern States. |
| D．There are more than 1, 000 tornadoes every year. |
| A．took place at the same time | B．were the biggest in history |
| C．came and went quickly | D．brought death and destruction |
| A．Tornado dangers and warning signs. | B．How to stay safe during a tornado. |
| C．Different kinds of tornadoes. | D．How a tornado forms. |
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【推荐1】The Earth set unofficial record high temperatures last week. Scientists said they were a clear sign of how pollutants released by humans are warming the environment. “Heat sets the pace of our climate in so many ways... it’s never just the heat,” said Kim Cobb. a climate scientist at Brown University.
Ocean warming, wildfire smoke and early arrived EI Nino that much of North America experienced this summer are other signs of climate troubles. Other recent natural events also show that climate change has entered new territory.
Most of the planet is covered by oceans, which have taken in 90 percent of the recent warming caused by planet-warming gases. In April, worldwide ocean temperature rose to 21, 1°C, which scientists believe was caused by a combination of planet-warming gases and the early EI Nino formation. EI Nino is a period of warning Pacific Ocean waters. Newly published data documented exceptionally warm ocean temperatures in the North Atlantic and also extreme sea heat waves near Ireland, Britain, and in the Baltic Sea.
High levels of wildfire smoke were more common on the US West Coast recently. Several rounds of smoke from wildfires in northern Canada brought dangerous air quality levels to eastern North America. Scientists say that climate change will make wildfires and smoke more intense and that the East Coast will see more of it.
The current EI Nino formed a month or two earlier than usual. It replaced La Nina that, with its cooling of Pacific waters, kept worldwide temperatures down. That means that it will have more time than usual to strengthen. It is predicted that there is a 98 percent chance that at least one of the next five years will be the warmest on record. One of these years would beat temperatures from 2016 when an exceptionally strong EI Nino was present.
1. What did Kim Cobb want to say in the first paragraph?| A．Cold wave might arrive soon. | B．The heat may come to an end. |
| C．The Earth would suffer more. | D．It’s easy to forecast the weather. |
| A．Ireland. | B．Britain. | C．The South Atlantic. | D．The US West Coast. |
| A．More earthquakes. | B．Fewer accidents. | C．Record heat. | D．Extreme cold. |
| A．Weather patterns. | B．Climate troubles. | C．Polluted waters. | D．Green practices. |
【推荐2】Earthquakes happen without warning. They can happen any time of a day, at any point during the year. But don’t worry because most are so weak that they cannot be felt. Only a few big ones hurt people. However, it’s important to know what to do when an earthquake is happening.
Do not go outside. You could get injured from falling glass or parts of buildings. If you are outside, stay away from buildings and power lines (输电线).
Stay under a desk, table, or other strong furniture. Hold on to it. Or stay in a corner of the building. Cover your face and head with your arms and cover your mouth with a towel or clothing. Stay inside until shaking stops and it is safe to go outside.
Keep away from windows, pictures or advertisements on the wall or the building, and anything else that could fall and hurt you. Most people get injured by falling things during an earthquake, not by the shaking itself.
Also keep away from a fire. You could fall down and burn yourself on the fire.
If you are driving when an earthquake happens, stop the car if it’s safe. Stay inside your car until the earthquake stops, and don’t drive near bridges. Try not to stop by power lines or trees. These could fall and hurt you.
1. Most earthquakes are too ________ to hurt people.| A．strong | B．weak | C．dangerous | D．heavy |
| A．run out of the building | B．stay in a corner of the building |
| C．cover your head with your arms | D．cover your mouth with a towel |
| A．How Earthquakes Happen | B．How to Drive a Car |
| C．What We Should Do in Earthquakes | D．Why Earthquakes Happen. |
【推荐3】The world has always had to face water-based natural disasters, such as tsunami and hurricanes. In an interview, Water Management Monthly talks to Dan Smith, who works in ‘disaster mitigation’ for a government ministry.
‘Dan, could you tell us what disaster mitigation means?’
‘Disaster mitigation means attempting to minimize the impact of natural disasters both before and after they happen. My department and work in two specific areas in order to try and do this: risk reduction and risk analysis. They are both equally crucial in disaster mitigation.’
‘What do you mean by risk reduction?’
‘Risk reduction means many things. It is not just referring to big engineering projects like dams. Often, small community projects can be the most effective means of risk reduction. The main way floods can be prevented is by the construction and maintenance of earth wall defences, or levees. These block the progress of rising water.
However, even the best levees can’t protect against the destructive power of a tsunami. In this case, early-warning systems are lifesavers. They can let people know as early as possible if there is likely to be flooding.’
‘What types of risk analysis do you do?’
‘Firstly, risk analysis concerns flood mapping, where we identify the parts of the country which are at most risk from flooding. Secondly, there is mitigation planning, which means helping local communities plan for when disaster strikes. Thirdly, we make sure that the country’s dams all work properly and are safe. Although many people criticize dams because of their environmental impact, there are many benefits to them too, such as hydroelectricity, irrigation, water storage, water sports and, of course, flood control. In terms of a cost-benefit analysis, we are definitely ahead.’
‘Do you think countries are better prepared now for natural disasters than they were in the past?’
‘Definitely. We are constantly developing new flood-prevention solutions. An example of one such measure can be found in the UK, with the Thames Barrier. This is an enormous engineering project designed to prevent London from flooding.’
‘Aren’t programmes like that very expensive? What lower-cost alternatives are there?’
‘Flood prevention does not have to be expensive. Sandbags, for example, can be a highly effective way of stopping flood water.’
1. The two aspects involved in minimizing the impact of natural disaster are _______.| A．the construction and maintenance of earth wall defenses |
| B．flood mapping and mitigation planning |
| C．risk reduction and risk analysis |
| D．small community projects and early warning systems |
| A．ensuring all dams are well functioning |
| B．developing new flood-prevention solutions |
| C．assisting communities in planning for when disaster strikes |
| D．identifying which parts of the country will be threatened by flooding |
| A．Individuals are better prepared for natural disasters now than before. |
| B．The city of London is at potential risk of flooding. |
| C．There are many low-cost flood prevention alternatives. |
| D．Despite the environmental impact of dams, they bring many benefits. |
【推荐1】With the global warming reaching catastrophic levels, this dramatic climate change is causing the warming up and melting of the Arctic, which has led to other potential dangers for nature there.
The danger is for an increase of pollution as well as exploitation (开采) by resource companies which are looking to drill in the area and approaching new sources of oil, gas minerals and hydropower. Shell has already revealed its plans to drill in the area, and so are other oil and gas drilling companies.
These new sources of fossil fuels will further increase harmful greenhouse gases causing permanent damage to the atmosphere, the weather and to the world and its population. The small and unique population and ecosystems of the Arctic are also threatened by the new dangers of pollution.
Recently Shell said that it is currently stopping is planned project for drilling in the Chukchi Sea, but unfortunately, the dangers are not all gone for this environmentally sensitive area. Another oil drilling company— Italian Eni has announced a 5.5 billion dollar oil drilling project for the Norwegian Arctic area.
Already, the impact on the environment in the Arctic is becoming evident and is being documented. The tundra (苔原) is disappearing rapidly as the frost is melting. The Inuit hunters are worriedly watching the sea ice disappearing, which is making sea animals such as seals change their behaviors and habits.
Overall, the climate changes in the area are now being considered as unpredictable and can cause a serious threat to the infrastructure (基础设施), the local people and the over 21,000 Arctic animal species.
With the increase of global temperature levels by an average of 2 degrees Celsius, this tendency is spreading to the Arctic as well. The level of the sea has risen by about 8cm since 2000. With the melting of the permafrost (永久冻土) in the area, a massive release of methane (沼气) in the atmosphere is expected, which can have a serious effect on the global weather.
1. What does the underlined word “catastrophic” in Paragraph 1 probably mean?| A．Controllable. | B．Practical. | C．Disastrous. | D．Steady. |
| A．In the Chukchi Sea. | B．In the tundra. |
| C．In the Norwegian Arctic area. | D．In the sea ice. |
| A．Cautious. | B．Doubtful. | C．Anxious. | D．Uncaring. |
| A．The Inuit hunters make sea animals change. |
| B．The climate and environment influence each other. |
| C．The Arctic animal species cause the great changes of the climate. |
| D．A release of methane has had a serious effect on the global weather. |
【推荐2】In many cases, online classes can be a gift to college students everywhere. They’re different from traditional classes in many ways, which can be a welcome relief for students.
One thing that many college students probably dislike about traditional in-person classes is that they’re inflexible. Whatever class you have, there is usually a specific schedule you need to follow and you must attend the class in person.
By contrast, online classes are much more flexible. They don’t require you to attend classes at a particular time, which means you have the opportunity to do your work whenever you see fit. Of course, this comes with a possible disadvantage if you aren’t the best at managing your time. However, if you are efficientat managing your own schedule and getting your assignments and studying done in a timely manner, then online classes are a great option for you. Flexibility with your classes gives you the chance to make time for other important things in your life.
Not only are online classes flexible, but they also offer a comfortable environment in which you can learn. Because you don’t have to physically attend classes, you’ll have the chance to work from wherever you want. So if you prefer learning and getting work done in a cafe, go to a cafe. If you would rather do your work in your bedroom, you have the freedom to do that.
Another great thing about online classes is that there are quite a variety to choose from. You can find practically any degree program you want online to help you advance in your education and career.
The costs of a college education definitely add up when you consider expenses for not only class credits, but also perhaps on-campus housing, textbooks, meal plans, and other fees. When it comes to online classes, however, you don’t have to worry about all those extra expenses. As a result, online classes may be a good choice if you’re looking to go down a more affordable route.
1. Which is the structure of the passage?A． | B． | C． | D． |
| A．Neutral. | B．Supportive. | C．Negative. | D．Critical. |
| A．Why online lessons are becoming popular |
| B．How one can make good use of online classes |
| C．Who can benefit greatly from online learning |
| D．What students love about taking online classes |
| A．Online educators. | B．University students. |
| C．Online masters. | D．Computer programmers. |
Directions： Read the following three passages. Each passages is followed by several questions or unfinished statements. For each of them there are four choices marked with A， B， C and D. Choose the one that fits best according to the information given in the passage.
A
As we all know， the Dragon Boat Festival is our country’s traditional festival， but do you know there is also a Dragon Boat Festival in South Korea， which also falls on May 5 of the lunar calendar(阴历)？ It has been reported that South Korea will apply to United Nations Educational， Scientific and Cultural Organization (UNESCO 联合国教科文组织) to make the celebration of the Dragon Boat Festival its own intangible cultural heritage (非物质的文化遗产). If successful， people from other countries may see the Dragon Festival as a Korean creation.
As the birthplace of the yearly event more than 2,000 years ago， China is not happy with the situation. “It would be a shame if another country successfully made a traditional Chinese festival part of its own cultural heritage ahead of China，” said Zhou Heping， deputy(副) culture minister. The Chinese Ministry of Culture is even thinking of making its own application(申请) to UNESCO， covering all traditional Chinese festivals， including the Dragon Boat event. It is thought that the festival is held in memory of the great poet Qu Yuan (340－278 BC)， who lived in the State of Chu during the Warring States Period. Qu was known to be a patriot (爱国者) and admired by ordinary people.
He is said to have jumped into Miluo River， because he had lost hope in his country’s future. When people heard about Qu’s death， they sailed up and down the river searching for his body. They also beat the drums to frighten away the fish and threw Zongzi into the water to stop the fish touching Qu. Dragon boat racing is said to come from this search for the poet’s body.
Over the years， the Dragon Boat Festival has spread throughout the world. In Japan and Vietnam， as well as South Korea， the festival has mixed with and become part of the local culture.
1. The Dragon Boat Festival .
| A．is also kept by South Korea |
| B．comes from South Korea |
| C．was created by South Korea |
| D．is South Korea’s cultural heritage |
| A．Fighting against South Korea. |
| B．Telling South Korea it’s not right to do so. |
| C．Considering to do the similar thing. |
| D．Asking South Korea not to do so. |
| A．In memory of Qu Yuan. |
| B．In memory of all the patriots of China. |
| C．To frighten away the fish. |
| D．In honor of QuYuan’s birthday. |
| A．feed him |
| B．protect his body from going bad |
| C．prevent the fish biting his body |
| D．attract his soul |
| A．a nationwide | B．a worldwide |
| C．an Asian | D．a foreign |
