flow lines

例句：

1. 1. The engineer drew a flow line on the diagram to show the fluid's movement.
   工程师在图表上画了一条流动线来表示流体的运动。
2. 2.The company has implemented a new system to improve its efficiency and reduce waste in the production process.
   该公司已经实施了一个新的系统，以提高其效率并减少生产过程中的浪费。
3. 3.The pipeline was designed to transport oil from the refinery to the storage tank.
   该管道设计用来将石油从炼油厂输送到储罐。