医生在检查前使用了药物来扩大她的瞳孔。

The doctor applied medication to induce ___dilation of her pupils before the examination.

医生用特殊的仪器测量了瞳孔的扩张情况。

The doctor used a special device to measure the ___dilation of the pupil.

数学课上，老师用圆形演示了图形放大和缩小的变换过程。

In math class, the teacher used a circle to demonstrate how ___dilation changes the size of a shape.