engine warm-up

例句：

1. 1.Before the race, the team leader warmed up the engine for a few minutes to ensure smooth operation.
   比赛前，车队队长对发动机进行了几分钟的预热，以确保顺利运行。
2. 2.During the warm-up, the athletes were seen stretching their muscles and warming up their bodies.
   在热身期间，运动员们被看到正在伸展肌肉并暖身身体。
3. 3. The engineers performed a thorough warm-up before starting the engine tests.
   工程师们在开始测试引擎之前进行了彻底的热身。