Spending just a few hours a week online may make people feel more socially isolated , lonely and downhearted , according to a two-year study of nearly 100 families with the Internet. "We were surprised to find that social technology has such bad effects on social communications," the lead author, Dr. Robert Kraut of Carnegie Mellon University in Pittsburgh, Pennsylvania, said in a statement to the news. The findings suggest that "Rather than encourage students to use the Internet alone for research, teachers might give pupils online group homework to complete with classmates. Local groups might build websites that allow neighbors to discuss local affairs ." "Before the technology develops and can be really more  _ , people shouldcontrol  their wishes to use much of the Internet," Dr. Kraut and other experts advise. In order to control their children and encourage family activities, parents might think of putting the computer in the living room rather than in a child's room, they suggest. Dr. Kraut also suggests that when surfing on the net, especially when chatting with strangers on the net, children should not use their real names, and that they should not tell the addresses, telephone numbers to the strangers. This study was made by    .
100 families Dr. Kraut and other experts the newspaper Dr. Kraut only