narstimulant

例句：

1. 1. The athlete's performance was enhanced by the narstimulant.
   运动员的表现因兴奋剂而得到提升。
2. 2. The drug is a narstimulant that can increase alertness and focus.
   这种药物是一种兴奋剂，可以提高警觉性和专注力。
3. 3. The use of narstimulants is strictly regulated in many countries.
   在许多国家，兴奋剂的使用受到严格监管。