海水的密度大于河水的密度,当军舰(保持质量不变)由大海驶向河流的过程中,它所受到的浮力将____ (选填“增大”、“不变”或“减小”),军舰排开水的体积将____ (选填“增大”、“不变”或“减小”)
— What time shall we leave for the airport? — It's foggy today. I'm not sure __________ be closed soon. Let's go now.
标志中国近代化开始的事件是( )