aperture of bridge

例句：

1. 1.The camera has a small aperture that allows only the most important shots to be taken.
   这台相机有一个小的开口，只能拍摄最重要的镜头。
2. 2.The scientist used a microscope with an aperture of 0.2 microns to observe the cells.
   科学家使用了一个具有0.2微米开口的显微镜来观察细胞。
3. 3. The hole in the wall is too small for a person to pass through.
   墙上的洞太小，一个人无法通过。