2019外研版高一英語(yǔ)必修一unit5課文

1、必修一 unit5Understanding ideasThe Monarchs Journey1. Many animals move from one place to another at certain times of the year. This annual movement is called migration. They migrate to find food, seek a partner, or in search of warmer weather. One of the most wonderful migrations in nature is that of

2、the North American monarch butterfly.2. Every autumn millions of these beautiful insects with a fine black and orange wings begin a long and difficult journey. Somehow they manage to travel around 4,000 kilometers south and find their way to California or Mexico. However, until recently no one knew

3、how they did this.3. A team of scientists led by Professor Eli Shlizerman at the University of Washington has now found the answer. They have found out that the monarch is able to tell the time of day. It uses its eyes to measure the position of the sun. These two pieces of I information-the time of

4、 day and the point where the sun is in the sky- allowed the butterfly to determine the way to go. Eventually, it manages to reach the places where it will spend the winter.4. The solution to the mystery of the monarchs amazing ability comes at a time when it is in serious trouble. Its population has

5、 crashed by as much as 90 percent in the last few years. Sadly, human activity is the main reason why the number of monarch butterflies is falling. In many of the places where the butterfly can be found, people are destroying the natural environment. They cut down trees and use chemicals that killed

6、 plants that monarch caterpillars eat.5. The research on the monarchs behavior has however led to a greater awareness of this creature. People have been working together to record its migration and make sure that there are enough plans for it to feed on. If this works, there may come a time when the

7、 number of monach butterflies increases once again. The more we know about this lovely creature, the greater the chance it will survive and keep its place in the natural world for a long time to come.Developing ideasAn Encounter with Nature1. As a nature photographer, I have to brave the elements. B

8、ut despite the wind and the rain I still enjoy working outside in the wild. One of the best things about this job is that you can observe animals in their naturalenvironment.2. My favorite place to take photos is Yellowstone National Park. As the worlds first national park, Yellowstone is famous for

9、 the variety of its wildlife, but it is probably best known for its bears. These huge, strong animals can live for 30 years. Despite a weight of up to 300 kilograms, they can run at a speed of around 64 kilometers per hour and are also excellent swimmers.3. Last spring in Yellowstone, I followed a p

10、ath that took me through a dark forest. When I finally stepped out of the trees, the view was breathtaking. An eagle flew over the snow capped mountains which were reflected in the still lake below. Well, I was concentrating on photographing this amazing scene, I suddenly had a feeling that I was be

11、ing watched. Slowly, and with the camera still held to my eye, I turned. and froze. Only meters away from me was a bear. With water falling off its thick, brown hair, the bear stared back at me. Time stood still as the bear and I both waited to see who would move first. My legs started shaking. Some

12、how, I forced my finger to press the button. A second later, the bear turned and ran back into the forest. When I recovered from the shock, I looked at my camera. My most frightening but magical experience was now captured forever in a single image.4. From time to time I looked at the photo as a rem

13、inder to show respect to all animals. It is after all we who are the visitors to their world.Writing an animal fact of fileThe red -crowned crane is one of the largest cranes in the world, standing at about 150 cm tall. Its feathers are as white as snow, except for some black ones on its face, neck and wings. Its unique feather, from which it gets its name is the bright red skin on the top of its head. The red- crowned crane is found in China, Russia, Mongolia, Japan and the Korean Peninsula. In China, it spends the warmer months in the rivers and wetl