题型:阅读选择 题类:模拟题 难易度:普通
2019初中英语中考复习专题训练卷(七)阅读理解(三)说明议论类
Why salmon will newer get lost
When you're packing for an adventure, what's the most important thing you'll need? If you don't want to get lost, you' need a map. Or better yet, a GPS. What about other animals? How do they know where they're going?
While humans depend on technology to travel, some animals have something far more advanced. Researchers, mainly from Oregon State University, US, found that Chinook salmon have a "built in GPS" of the Earth's magnetic field(磁场). This means as soon as they are born they are able to direct themselves in the ocean. It acts like a big map inside their brain.
Scientists placed some baby salmon into a big swimming pool. To simulate the Earth's magnetic field, they put magnetic coils(线圈) all around the pool. Then, by changing the direction of the coils, the salmon began to change their own direction. They started to face in the direction of their ocean feeding area. This is a safe place in the ocean where salmon can find food to eat. When the scientists changed the coils to the opposite side, the salmon also turned in the opposite direction. Just by using their "built-in GPS", the salmon were able to figure out the direction of their feeding area.
How did Chinook salmon get their "built in GPS"? The scientists believe that their navigation(导航) skills came through evolution(进化). The fish that were able to reach the feeding area lived longer. Then they could pass on their navigation skills to their babies. So if you're ever lost and in need of some help, maybe you should ask a salmon to point you in the right direction!
between,speed,its,look,complete |
An "air taxi" seems like science fiction, but believe it or not, you'll be able to take one in the near future.
On February 27, an eVTOL aircraft completed {#blank#}1{#/blank#} first test flight (飞行) in Guangdong. The whole trip took only about 20 minutes from Shenzhen to Zhuhai. The flight will provide a faster choice for people to travel {#blank#}2{#/blank#} two cities.
The eVTOL aircraft {#blank#}3{#/blank#} like a small plane. But unlike a plane, it doesn't need a long runway. This new aircraft is {#blank#}4{#/blank#} powered by electricity. It can fly for 250 kilometers on a single charge (充电). It can carry up to five people at a {#blank#}5{#/blank#}of up to 200 kilometers per hour. If everything goes well, it hopes to start carrying passengers in 2026.
Inventions are very important and they can easily change our life. The followings are some great inventions.
The television was invented in 1925. As time passed,more and more people were able to buy the television. It is a popular invention,but it is also bad for your eyes. People spend almost 4~8 hours in front of a TV while they spend less than 2 hours staying with their family. | The plane was invented in 1903. It is a very popular way of going out either for travelling or business. Over 3,000,000 people take a plane every day. It is very convenient for us. And it makes our trip faster and more comfortable. But the biggest problem led by the planes is the air pollution. |
Credit cards were started in 1915. They allow people to buy things first and pay for them later. What's more,you don't have to carry lots of money around. You can know what you have bought by credit cards. However,you may not know how much money you have spent until you get your bill. This might put many young people and families into an economic crisis(经济危机). | The pacemaker(心脏起搏器) began to be used in 1932. It saves many people's lives. It was an invention that was designed to give the heart small "shocks" and make it work again. The only disadvantage(缺点) for most people is that it costs a lot of money. Getting one can cost from 16,500 yuan to 35 |
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