The power of nature Wind, water, fire and ice-these powerful natural forces shaped the land of America
in the past. They are still changing it today.
     The Colorado River slowly cut through stone to make the Grand Canyon.
     Long ago, ice sheets cut Yosemite Valley and glaciers (冰川) were moving in Alaska.
     Rains and storms hit the land from time to time. Fires sometimes burn down forests and destroy the homes
of wide animals. This happened in Yellowstone Park in 1998.
     Dead volcanic (火山的) mountains such as Haleakala on Moui and Crater Lake in Oregon are beautiful to
look at. There are also several active volcanoes in the US, especially along the Pacific Coast. There are also
many earthquakes in this area. Scientists can do nothing to control earthquakes or volcanoes. This was shown
clearly on May 18, 1980. At 8: 32 that morning, Mount St. Helens in Washington State erupted (爆发). The top
of the mountain was blown off.
     Over 60 people-campers, scientists, journalists, and forest workers were killed. Hundreds of square miles
of forests were knocked down. In towns over 100 miles away, day suddenly became night. An ash cloud hid
the sun for many hours. Town and fields in Washington, Oregon, and Idaho were covered with dirty grey ash.
     Scientists knew that Mount St. Helens could erupt soon but no one could say when. And no one expected
the terrible strength of the eruption. Many people were surprised and weren't ready. Harry R. Truman, 84,
owned a small hotel in Mount St. Helens. Scientists had asked him to leave because the volcano was becoming
dangerous.
     Harry Truman would not leave his home. Now it is covered with many feet of dirty ash. A small cross
stands above the place where Harry probably died. Perhaps it is better that he did not see what happened to
Mount St Helens, the once beautiful lake, and the forests.
     But slowly, life is returning to the dead area around the mountain. Grass and small plant are beginning to
grow again. Deer and birds have been seen in the area. The land will never be the same as it once was. Perhaps
Mount St. Helens will erupt again but this is all part of nature's pattern of change, and man has little power to
control it. 

根据短文内容，判断下列各句的正(T)误(F)。
(     )1. The Colorado River slowly cut through stone to make the Grand Canyon.
(     )2. Long ago, ice sheets made Yosemite Valley and the Great Lakes, and glaciers are not moving in Alaska.
(     )3. Scientists knew exactly when Mount St. Helens would erupt.
(     )4. Harry was finally persuaded to leave his home.
(     )5. Now the land is not the same as it once was.