Verbs can be said to have five forms in English: the base form, the present tense form (which may include the agreement ending -s), the past tense form, the present participle, and the past participle. Although the forms are predictable for most verbs in English, many common verbs have one or more unpredictable or irregular forms.
Base form: study
Present tense form: studies
Past tense form: studied
Present participle: studying
Past participle: studied
