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how to master skills for the toefl ibt listening advanced part 41

To see a list of possible assigned topics, go to www.toefl.org and download the entire list. To help yourself become familiar with the topics, try to break them down Into categories such as the following: | are resistant to the fungus. Even when they re infected they rarely die. This is because they have two genes that are resistant to chestnut blight. The foundation made simple hybrids of susceptible American trees wrtn Asian trees. The results showed that the hybrids carried at least two genes resistant to chestnut blight. Then they started back-crossing where the partially resistant hybrid trees were then crossed with the susceptible American trees. One fourth of the progeny inherited both of the resistant genes and was therefore resistant These are then crossed with the American trees. This back-crossrng process will be repeated over and over so that the percentage of American genes in the hybrids increases and insures passage of the resistance genes. Eventually a final cross will be made between a pair of trees carrying two resistant genes. One out of sixteen of these trees win have four resistance genes making them fully resistant to the blight fungus. In short the foundation is breeding the trees for resistance to blight. Its goal is to reintroduce within the next tew decades the blight-resistant American chestnut tree to the forests of eastern North America. species Some scientists believe this canopy afone may contain half of the world s species 1. It had a b g emphasis on nature. It very vividly described the beauty of nature. 2. Rainbow 3. He enjoyed nature and the outdoors. Okay during our last class we began to discuss a new form of poetry romanticism. And we also read a beautiful poem. Rainbow by William Wordsworth who ushered in the romanticist movement in the late 18th century. The emphasis among these poets was on nature. The romanticists were a back-to-nature movement. Their poems were not concerned abouf politics current events or with truth and reason. They wrote about the mountains the rivers and the sea. They tried to capture nature s beauty and did it very vividly Wordsworth himself really enjoyed the outdoors and spending his time in natural .