impulse source

例句：

1. 1. He felt a sudden surge of excitement as he heard the news.
   他听到这个消息时，突然感到一阵激动。
2. 2.The car's engine revved up to full throttle.
   汽车的引擎全速运转。
3. 3. Her impulsive decision cost her dearly.
   她一时冲动的决定让她付出了沉重的代价。