fluid sensor

例句：

1. 1. The liquid inside the container is moving due to gravity.
   容器内的液体由于重力而移动。
2. 2. The scientist used a special device to measure the fluid properties of the substance.
   科学家使用一种特殊的装置来测量这种物质的流体性质。
3. 3. The liquid level in the tank needs to be checked regularly to prevent overflow.
   需要定期检查油箱中的液位，以防止溢出。