Every four to ten years something happens to the weather system of the Earth. Everything changes, and scientists don’t know why. The low - pressure area moves toward the east, the high - pressure area is very weak, and the winds blow toward the east. A great pile of warm surface water moves toward South America. People call this “El Nino”. It usually happens at Christmas time, and El Nino is the Spanish name for the baby Jesus.
Usually, the effects of El Nino are very mild. However, the one that started in 1982 was different from the other recent ones. It had a very powerful effect on the world’s climate. It caused huge changes in the ocean currents. It caused floods in some areas and droughts in others. There were terrible windstorms and huge ocean waves swept houses into the sea. El Nino did billions of dollars worth of damage. Thousands of people lost their lives and thousands of others were homeless.
In 1983, the winds, ocean currents, and pressure areas started to become normal again. Meanwhile, scientists throughout the world organized research to learn more about El Nino. They are using satellites and research boats to observe the atmosphere and the ocean. It is a very complicated problem, but if the scientists of the world work together, they should be able to learn the causes of El Nino. Then they will be able to predict what will happen and work to prevent a repeat of the death and destruction of 1982 - 1983.

Today, computer companies sell many different programs for computers. First, there are programs (46) doing math problems. Second, there are programs for scientific studies. Third, some programs are like fancy typewriters. (47) are often used by writers and business people. Other programs are made for (48) in schools and universities. And finally, there are programs for fun. They include word games and puzzles for children and adults.
There is a wide (49) of wonderful new computer programs, but there are other reasons to like computers. Some people like the way computers hum and sing when they are working. It is a happy sound, like the sounds of toy and childhood. Computers also have lights and pretty pictures. And computers even seem to have personalities. That may sound strange, but computers seem to have feelings. Sometimes they seem happy, sometimes they seem angry. It is easy (50) they are like people.