excitants

例句：

1. 1.The athlete was given an injection of the latest excitant before the race.
   在比赛前，这位运动员被注射了最新的兴奋剂。
2. 2. The drug is believed to be an excitant that can increase alertness and focus.
   这种药物被认为是一种可以增加警觉性和专注度的兴奋剂。
3. 3.Excitants are often used in sports to enhance performance.
   兴奋剂通常用于体育中以增强表现。