US Military Christens Self-driving Warship

音频下载[点击右键另存为]

upgrade – n. to make something better by including the most recent information or improvements

diesel – n. a type of engine that uses diesel fuel rather than gasoline and that is used especially in large vehicles

aircraft carrier – n. a military ship that has a large deck where aircraft take off and land

christening – n. the official ceremony in which something, such as a ship, is named