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 21^st 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.

历史分期是通过划分历史时期研究史学的一种方法，旨在揭示不同历史时期或阶段之间的质的差别，从中发现历史发展的特点及规律。阅读材料，结合所学知识回答问题。

关于中国近代史和中国现代史的分期，是确定中国近代史学科对象的重要问题。新中国成立以后，胡绳发表文章将其限定在1840—1919年之间。此后，中国史学界出现了中国近代史和中国现代史的明确分界，分界线就是1919年发生的五四运动。但范文澜等学者提出，按照社会性质，中国近代史应该包含1840—1949年的整个时期。

——据张海鹏《中国近代史和中国现代史分期应以1949年为界》

问题：

2015年米兰世博会举办期间，世博园中国馆举办“中国茶文化周”活动，向世界传播中国悠久的茶品牌和茶文化，纪念中国茶参加世博会一百年。开展这一活动有利于（   ）

①促进世界各国茶文化融合统一               

②使中国茶文化成为世界的主流茶文化

③中国茶文化与其他各国优秀茶文化相互交流借鉴

④促进中国茶文化的繁荣和发展

2008年5月31日，牙买加短跑运动员博尔特在纽约锐步田径大奖赛上以9秒72的成绩跑完了100m。他在100m决赛时的平均速度大约为 （  ）