Choose the suitable word to fill in each plank.

Today, computer companies sell many different programs for computers. First, there are programs for doing math problems. (26)______, there are programs for scientific studies. Third, some programs are like fancy typewriters. They are often used by writers and business people. Other (27)______are made for courses in schools and universities. And finally, there are programs for fun. They include wordgames and puzzles for children and adults. There are many wonderful new computer programs, but there are other reasons to like (28)_____. Some people like the way computers hum and sing when they (29)_____. 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 (30)_____they are like people.

Today, computer companies sell many different programs for computers. First, there are programs for doing math problems. (26)______, there are programs for scientific studies.