Final answer:
A progressive verb form indicates an ongoing action or event. It is formed by combining a form of the verb 'to be' with the base form of the main verb and adding -ing.
Step-by-step explanation:
A progressive is a type of verb form that indicates an ongoing action or event. It is formed by combining a form of the verb 'to be' (am, is, are) with the base form of the main verb and adding the -ing ending. Examples of progressive verb forms include 'I am reading,' 'She is running,' and 'They are playing.'
Learn more about Progressive verb form