gradient-board

例句：

1. 1. The engineer used a gradient board to calculate the slope of the road.
   工程师使用梯度板来计算道路的坡度。
2. 2.The student needed a gradient board to help them understand the concept.
   学生需要梯度板来帮助他们理解这个概念。
3. 3.The teacher gave the students a gradient board to practice their problem-solving skills.
   老师给学生们一个梯度板来练习他们的问题解决技能。