What's more, this function is actually linear, since it passes our visual test that any line of evenly spaced dots remains evenly spaced once it lands on the number line.

更重要的是 这个函数实际上是线性的 因为它通过了我们的视觉测试 即任何等距点组成的线一旦落在数轴上 就会保持等距。