M Y SISTER AND I DO NOT STUDY AT THE SAME SCHOOL. THAT IS THE REAS...

80. M y sister and I do not study at the same school. That is the reason for why my father has bought 2 bikes. A B C D Phần 4. In the past people used to have all sorts of strange ideas. They used to think that the earth was like a flat board. They were absolutely certain that it was possible to fall off the end. They used to believe that the earth was the center of the universẹ They thought the sun moved around the earth. Together with the progress of science and technology, people’s knowledge of the universe has changed. We are now living in a small planet among millions of stars in the huge universẹ Men have been interested in the starts even since the time when they first looked up into the skỵ Some of these starts may have their own planets. They can also suppose that intelligent life may exist on one of them. The problem is that the nearest star is four light years awaỵ In other words, light from it has been traveling for four years when it finally reaches us. Probably nobody from the earth will ever visit that star because it would take a rocket a lot of years to reach it.