相机的光圈决定了进入镜头的光线量。

The camera's ___apertures determine how much light enters the lens.

医生检查时发现他的瞳孔在强光下收缩得很小。

The doctor observed that his ___pupils became very small under bright light.

相机的光圈可以调整来控制进光量。

The camera's ___apertures can be adjusted to control the amount of light entering.