多项选择题The world's five major palaces are ______________. A、the Palace of Versailles in France B、the Kremlin Palace in Russia and the White house in America C、the Forbidden City in China and Kensington Palace in UK D、Buckingham Palace in UK and the Forbidden City in China
单项选择题()— 确保列车的运行速度在许可范围内 A. 间隔控制 B. 速度防护 C. 安全防护