There have been many great inventions that change the way we live. The first great (16) was one that is still very important today—the wheel. This made it easy for man (17) heavy things and to travel long distances. For hundreds of years after that, there were (18) inventions that had as much effect as the wheel. Then in the early 1800’s the world started to change (19) . There was little unknown land left in the world. People did not have to explore much any more. In the second half of the 19th century many great inventions were made. (20) them were the camera, the electric light and the radio. These have all become a big part of our life today.
The first part of the 20th century saw more great inventions. The helicopter in 1909. Movies (21) sound in 1926. The computer in 1928. And jet planes in 1930. This was also a time when a new (22) was first made. Nylon came out in 1935. It changed the kind o
A. scientist
B. artist
C. musician
D. invention
Throughout history there have been many unusual taxes levied on such things as hats, Beds, Baths, marriages, and funerals. At one time England levied a tax on sunlight by collection from every household with six or more windows. And according to legend, there was a Turkish ruler who collected a tax each time he dined with one of his subjects. Why To pay for the wear and tear on his teeth!
Different kinds of taxes help to spread the tax burden. Anyone who pays a tax is said to "bear the burden" of the tax. The burden of a tax may fall more heavily on some persons than on others. That is why the three levels of government in this country use several kinds of taxes. This spreads the burden of taxes among more people. From the standpoint of their use, the most important taxes are income taxes, property taxes, sales taxes, and estate, inheritance, and gift taxes. Some are used by only one level of government; others by two or even all three levels. Together these dif
A. the inconvenience for him to put on and take off clothes
B. the damage that eating did to his teeth
C. his efforts to cut the food into pieces
D. the decay of his teeth because of sugar
Through history there have been many great explorers. Have you, for example, heard of Mar co Polo, the famous Italian traveller He was one of the first Europeans to travel to China. He arrived in China in the late 13th century. About 200 years later Christopher Columbus sailed from Spain by ship. He was looking for a new way to reach India. However, as you probably know, he did not reach India. He landed in America. Five hundred years after Columbus, in the 1930s, a famous explorer named Richard Byrd was one of the first persons to fly over both the North and the South Poles.
Today we continue to explore this world, and are starting to explore other worlds, too. In the late 1950s and the 1960s Russian and American scientists sent many unmanned spacecrafts to the moon. These spacecrafts sent back valuable information about the moon. Then on July 16,1969, the first manned spaceship to the moon left earth. On that day Apollo 11 blasted off with three American astronauts on b
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