vane number

例句：

1. 1. The vane number on the windsock indicates the direction of the wind.
   风筒上的风向标指示风的方向。
2. 2. The vane number on the weather balloon is used to determine the wind speed.
   气象气球上的风向标用于确定风速。
3. 3. The vane number on the radar screen helps us to track the movement of the storm.
   雷达屏幕上的风向标帮助我们追踪风暴的运动。