Verbs tell activities, faculties, or states, for example to think, to work, or to be. They may do this in three forms and four Aspects.
Most dictionaries list irregular verbs alphabetically. We list them looking to speech sound patterns. This can make remembering irregular forms easier.
American is not a monolith: it has regional varieties, and these have 2nd and 3rd forms of the same shape more often.
The appendix is to help visualize all patterns for all Aspects in grammatical time, the Present, Past, or Future.
The toolkit here can work onscreen, for real-time use. The resource is free to use with Travelers in Grammar; it opens with Microsoft PowerPoint.