For many employers, Facebook, MySpace and other social networking sites are already a threat （威胁） that cut into productivity．Now they have something else to worry about—the s hosted by these sites． This new type of social gaming is called "asynchronous" gaming and allows people to play with their friends without having to be online at the same time．The low-intensity （低强度） engagement has made s such as FarmVille, Cafe World and Pet Society popular among employees who often log on during office hours． "What we are seeing is that more and more people and organizations are recognizing the productivity lost so probably more chief information officers are blocking Facebook applications," Rebecca Wettemann of Nucleus Research said． Boston-based Nucleus Research, which conducted a recent study into the effects of social networking sites on productivity, said nearly half of office employees in the United States access social networking sites at work, which leads to an average loss of 1．5 percent of total office productivity． Facebook, which has 350 million users, says at least 20 percent of its members play s online．Sebastien de Halleux, CEO and co-founder of online creator Playfish, said Asia is growing at a faster pace than other regions．"We had no idea that it would spread so fast．．．when we had 100,000 users after one month, we thought it was the biggest success ever．Now with 60 million users we think this is only the beginning of something much bigger," he added． Zynga's FarmVille, the best known with over 70 million active users to date, allows players to own a virtual farm where they can grow crops and raise animals． While companies try to limit access to social networking sites, not everyone sees the s as harmful． 61．We can learn that Pet Society is a _____． A．popular among employers B．without having to be online C．merely played during office hours D．that can be played online at a different time 62．It can be inferred from the passage that ____． A．Playfish is owned by Sebastien and Rebecca B．Playfish has over 70 million active users to date C．Asia will be the largest potential market for Playfish D．Playing online s loses 1．5 percent of total office productivity 63．The best title of the passage would be ____． A．Social Network Gaming B．New Threat to Productivity C．Social Networking Sites D．Latest Survey on Productivity ．What would most probably be discussed next after the last paragraph? A．Opinions in favor of online s． B．Measures to limit access to social networking sites． C．Suggestions on how to improve productivity． D．More examples about the bad effects of online s．