2 . TV was one of the greatest inventions in the 20th century. Nowadays, nearly every house has at least one TV set.

Television came into being based on the inventions and discoveries of many scientists. On April 7, 1927, the first public television programme was broadcast in the USA. The signals were received on a very small screen. It was only about the size of a business card. The pictures were reddish (微红色的) and not clear.

In the 1930s, bigger screens appeared with black-and-white pictures. However, a snowy picture was the best many TV viewers could hope for. Often, they could only get one station, and only when the weather conditions were good.

When World War II(1939~1945) began, the development of TV stopped. There were a very small number of TV sets in the hands of the public. By 1945, there were fewer than 7,000 working TV sets in the USA. A TV set cost about half the price of a car at that time.

The time after World War II is considered one of the golden periods of television. Families saved money during the war years, and wanted to buy a lot of things after the war. TV sets were soon put onto the “must-have” list.1950~1959 was an exciting period for television. Colour television and remote (遥控的) controls came out during this time. By 1955, the cost of TV sets came down a lot. Instead of being equal to half the price of a car, they were now just equal to the cost of a new set of tyres (轮胎). This marked the beginning of the booming age of TV.