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then early shellfish developed. Next green plants began to grow on land, and they were followed in time by land animals such as insects and amphibians. Still later, reptiles appeared for the first time. After that huge dinosaurs developed, too. They existed on the earth for over 140 million years. They became extinct probably because an unexpected incident broke out. 4. My friend John is now studying astronomy at college and wants to be an astronomer after graduation. Unlike other students, he once questioned whether there were eight planets in the solar system. He believed in religion, and even put up a theory quite different form the “Big Bang”. 5. Recently, in order to work out the puzzle of climate warming, many physicists, biologists and geologists attended an important meeting. They discussed how to prevent human beings from putting too much carbon dioxide into the atmosphere. Now that this a manmade problem man should solve it himself. 6. Several billion years after the “Big Bang”, the earth finally turned from a violent cloud of dust into a solid globe. Then the presence of water, many scientists believe, allowed the earth to dissolve harmful gases and acids into the oceans and seas. This produced a chain reaction, which made it possible for life to develop.7. Once, a et crashed on the earth and then exploded. The explosion blocked out the sunlight, so that the smog and steam floated in the air for some time.8. The following is a fictional story. Once upon a time, there were three great scientists named Isaac Newton, Albert Einstein and Stephen Hawking, who travlled in the cabin of a spaceship to the moon. They cheered up because they wanted to feel how the pull of the earth’s gravity would change during their journey. Besides, they observed stars and planets by analyzing the information sent by the satellite. During the whole trip they in their turn watched out for any possible change.1. How much do you know about Canada? The following quiz is very interesting to answer. What language(s) do the Canadians speak? Vancouver, Toron
