n. a base hit on which the batter stops safely at second base
n. a stand-in for movie stars to perform dangerous stunts
n. someone who closely resembles a famous person (especially an actor)
n. a quantity that is twice as great as another
n. 两倍
a. 两倍的, 双重的
vt. 使加倍
vi. 加倍, 代替, 快步走
[计] 双精度型
1. I need to double my efforts to finish the project on time.
我需要加倍努力，以按时完成这个项目。
2. The recipe calls for double the amount of sugar.
这个食谱需要双倍的糖量。
3. She has a double major in biology and chemistry at university.
她在大学里主修生物和化学，获得双学位。