sandwich board

例句：

1. 1.The teacher used the sandwich board to explain the math problem.
   老师用三明治板来解释数学问题。
2. 2.The chef used a sandwich board to display the menu.
   厨师用三明治板来展示菜单。
3. 3.The students used the sandwich board to draw their drawings.
   学生们用三明治板来画他们的画作。