孔径

例句：

1. 1. The hole in the wall is too small to fit through.
   墙上的洞太小，无法通过。
2. 2. The machine has a large diameter for easy cleaning.
   这台机器有较大的直径，便于清洁。
3. 3. The diameter of the pipe is 10 cm.
   管子的直径是10厘米。