Regular verbs in English add -ed to the stem for the past tense and the past participle. Example: help, have helped. Irregular verbs have different spellings, different vowels or a completely different word. e.g. to go went gone
regular verb
infinitive - to live
past tense - lived
present perfect - have lived
irregular verb
infinitive - to give
past tense - gave
present perfect - have given
Some verbs are regular in US English and irregular in British English
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