Thomas Edison was one of the (11) ______ inventors of the world. He was responsible for more than one thousand (12) _____ including the electric light bulb and the record player. He also created the world’s first industrial research laboratory. Edison was born in 1847 in Ohio, USA. When he was 10 years old, he set up a small laboratory after he (13) _____ a science book his mother showed him. In 1869, he borrowed some money and began to make inventions. In 1876 he built a new laboratory so that he could spend all his time inventing. He planned to turn out minor inventions every ten days and “big trick” every six months. He developed many devices that brought great (14) _____ to people’s life. He once said that the value of an idea lay in the using of it. Edison died in 1931, after having a remarkably productive life.

(11)

Water pollution is the contamination of bodies of water such as lakes, rivers, oceans, and groundwater (the water beneath the Earth’s surface). It is one of the most serious types of pollution.

Water pollution can have many different causes. Factories dump industrial waste into lakes and rivers. Sewage from households is another cause. Farms using pesticides to kill insects and herbicides to kill weeds can also lead to water pollution. These factors cause ‘point source’ pollution while pollutants from storm water and the atmosphere result in ‘non-point source’ pollution.

Water pollution can have dramatic effects. In many poor nations, there are frequent outbreaks of cholera and other diseases because of people’s drinking untreated water. Humans can even die if they drink contaminated water. Polluted water also causes the death of aquatic animals such as fish, crabs, or birds. Other animals eat these dead animals and may also get sick addition, herbicides in water can kill aquatic plants and cause further damage to the environment.

Choose the word that is of the different topic (or part of speech) from the others.