![Membean Word Root Of the Day show](https://d3dthqtvwic6y7.cloudfront.net/podcast-covers/000/025/719/small/membean-word-root-of-the-day.jpg)
Summary: Prefixes often undergo spelling changes depending upon the stem to which they are affixed. The prefix *in*, for example, can exist in the following forms: *il*, *im*, *in*, *ir*, and *ig*. Examples of words containing such forms include [*il*]legal, [*im*]bibe, [*in*]nate, [*ir*]regular, and [*ig*]noble.