王教授：
为庆祝外语系成立30周年，系决定于“9月3日举行庆祝会”。我们热诚请您前来参加庆祝会。庆祝会将在外宾楼(Foreign Guest House)餐厅举行。时间定为9月2日，上午9点30分开始，下午4点结束。当日活动安排如下：
上午9点30分至中午11点30分期间，系主任致欢迎辞，副主任将汇报我系所取得的成绩；中午12点至下午2点，午饭。下午2点至4点，在骑士俱乐部(Knight Club) 举行音乐茶话会。
请尽快回信。

A．Diving (underwater), act of entering water and remaining below the surface to explore, to work, or simply to have fun.
B．Diving (underwater), act of exploring water below the surface.
C．Diving (underwater), act of jumping into the water, the most common form of diving is sport diving, or recreational diving.
D．Diving (underwater), act of going into water and remaining above the surface to explore, to work, or simply to have fun.