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Directions: After reading the passage below, fill in the blanks to make the passage coherent and grammatically correct. For the blanks with a given word, fill in each blank with the proper form of the given word; for the other blanks, use one word that best fits each blank.The Lights of Aurora
On the night of 2 September1859, the dark sky over Europe and North America was suddenly full of light! The light did no come from the sun or the moon and it had a strange colour. The light moved across the sky, 1 (come) and going, like clouds in a strong wind in the United States, a man in Boston was using the telegraph to speak to a man in Portand 160km away. They both turned off the electricity for the telegraph, but 2 could still speak to each other for the next two hours. The electricity was coming from the light in the sky. How was this possible? And what was the light in the sky?
The light is called the aurora. Usually, you can see it only at the very north of the earth, 3 it is called aurora borealis or Northerm Lights, or at the very south, where it is the aurora australis or Southern Lights. But in 1859, something happened in the sun — a very large storm — and it moved the aurora across the middle of the earth. We do not think that his ever happened before 1859, and we know that it 4 (not happen) since then.
Why does the aurora happen? And why can we only see it at the top or bottom of the earth? The aurora is made by something 5 (call) the ‘solar wind’( wind from the sun). We cannot see this wind, or touch it. It is a wind of particles that travel away from the sun at the time at about 400 kilometers a second. Most of the particles never touch the earth. The earth has a kind of ‘wall’ around it that defends it 6 these particles. This wall is called the earth’s magnetic field, and it pushes the particles away on either side. But the earth's magnetic field has two “windows” in it: the magnetic north, and the magnetic south. At these places. the earth’s magnetic field turns down into the earth. And some of the particles from the solar wind come through these magnetic ‘windows’. These solar particles crash is to the particles that are already in our sky. And 7 this happens, we see the beautiful lines or clouds of light of the aurora.
Alaska is a good place 8 (see) the auurora borealis, and you can also go to places like Iceland, Siberia, the north of Greenland, Norway, Sweden, and Scotland to see the aurora australis, go to the south of Australia, Tasmania, or New Zealand.
People travel thousands of kilometers to see the aurora, and they can never be sure 9 it will happen. But 10 do see it says that they will never forget it.
