阅读下面材料，在空白处填入适当的内容（1个单词）或括号中单词的正确形式。
Today so many people are talking about AIDS, for which, ____ (fortunate)，there is no cure now. When we talk about its influence on our society, this disease is ____ most severe public health problem of all that we are facing in the 21st century. It is spreading at a(n) ____ (surprise) speed, especially in Africa.
The UN AIDS organizations have come to the ____ (conclude) that in the past 20 years, 20 million people have died of AIDS. And this figure will be three times bigger in the next two decades ____ measures are taken in poor countries. Only if people change their basic behavior in time, can AIDS ____ (stop) from spreading. For example, in San Francisco, the rate fell greatly when a serious program was carried out. People were ____ (please) to change their behavior when they realized how serious a risk they were taking.
Experts think in order to get the message across to those ____ don't realize the seriousness of AIDS, a well ____ (design) educational campaign is the only thing at the moment that can help. It would be criminal not to put it into practice. So everyone has a share of responsibility in the fight ____AIDS.
