numerical indicator tube

例句：

1. 1. The numerical indicator tube is usedto indicate the temperature of the liquid.
   数字指示管用于指示液体的温度。
2. 2. The engineerused a numerical indicator tube to measure thedistance between two points on the map.
   工程师使用数字指示管测量地图上两点之间的距离。
3. 3. The numerical indicator tube was used todisplay the results of the experiment.
   数字指示管用于显示实验的结果。