How are verbs inflected for aspect in English?

There are four different types of aspect in English: simple, perfect, progressive and perfect progressive. The perfect aspect is used for actions that have been completed, while the progressive shows that an action is ongoing. Below are the processes by which different aspects are formed in English, with examples in present tense.Simple: The verb in its bare form.I eat and apple.Perfect: the tensed form of "to have" with the past participle of the main verb.I have eaten an apple.Progressive: the tensed form of "to be" with the present participle of the main verbI am eating an apple.Perfect progressive: the tensed form of "to have", the verb "been" and the present participle of the main verb.I have been eating an apple.