bulb of level

例句：

1. 1.The sun is shining at the bulb of level.
   太阳在水平线上照耀。
2. 2. The boat was drifting at the bulb of level.
   船在水平线上漂移。
3. 3. The car was parked at the bulb of level.
   汽车停在水平线上。