Unit2 Section Ⅱ Grammar and usage & Integrated skills（作业）-2022-2023学年新教材高中英语必修第三册【精讲精练】牛津译林版

[限时检测] [限时30分钟] Ⅰ.阅读理解 Along the Ring of Fire Off the coast of Alaska，heated liquid rock rises through cracks (裂缝)in the floor of the Pacific Ocean. This superheated material known as lava (熔岩) flows like toothpaste. Stretching and erupting, the earth slowly builds a new island. Along the Pacific coast of South America, one part of the planet's surface gradually moves toward another. Although difficult to believe, the rocky outer surface of Earth is not hard；rather，it is broken up into huge pieces called plates.Up to 250 miles thick，the plates，which float on top of a softer layer (层) of hot rock, move at a pace of 0.39 to 3.94 inches per year.As the plates slide past one another，the action can sometimes result in volcanic activity. These events take place thousands of miles apart，yet they are connected.Surrounding the Pacific Ocean is a circle of volcanoes that includes more than half of the world's active volcanoes.This region is called the Ring of Fire. The Ring of Fire stretches from the west coast of South America northward to Alaska.It curves (成曲线形) left at the Aleutian Islands and crosses the Pacific Ocean. Then it heads down the east coast of Asia toward New Zealand. Major volcanic eruptions along the Ring of Fire make history. In 1883 Krakatoa erupted in four explosions. The third explosion was so loud that it could be clearly heard 3，000 miles away. Krakatoa threw a large dust cloud nearly 50 miles into the air. For a year，that cloud 　shrouded　 Earth and changed the weather worldwide. Closer to home, Mount St. Helens, a volcano in the Cascade Range in Washington, erupted in 1980.No lava flew from Mount St.Helens. But the ash was thick enough to affect travel. The side of the mountain fell away, causing a landslide. In 1991，Mount Pinatubo in the Philippines erupted after 600 quiet years. During four days in June，Pinatubo released more than 20 million tons of dust into the air, destroying many homes. Some volcanoes erupt more quietly, with lava flowing thro