Penguin - English irregular verbs trainer.

All verbs of English, whether regular or irregular, have five forms [often called principal parts]. These forms are the infinitive, simple present, simple past, past participle, and present participle.

The difference between a regular and an irregular verb is the formation of the simple past and past participle. Regular verbs are dependably consistent—the simple past ends in ed as does the past participle.

Irregular verbs are common verbs in the English language that do not follow the simple system of adding “d” or “ed” to the end of the word to form the past tense. That means the spellings can be a little tricky. Some irregular verbs follow patterns, such as drink–drank, spring–sprang, know-knew, and blow-blew but you can’t use those patterns with predictability. Learning irregular verbs means memorization.