The best example of this might actually be Wikipedia. There is a separate set of articles in a simpler and controlled form of English: https://simple.wikipedia.

The best example of this might actually be Wikipedia. There is a separate set of articles in a simpler and controlled form of English: https://simple.wikipedia.org/wiki/Main_Page https://simple.wikipedia.org/wiki/Main_Page , and details about the rules: https://simple.wikipedia.org/wiki/Basic_English https://simple.wikipedia.org/wiki/Basic_English