Verbs constitute one of the main parts of speech (word classes) in the English language. Like other types of words in the language, English verbs are not heavily inflected. Most combinations of tense, aspect, mood and voice are expressed periphrastically, using constructions with auxiliary verbs.
Generally, the only inflected forms of an English verb are a third person singular present tense form ending in -s, a past tense (also called preterite), a past participle (which may be the same as the past tense), and a form ending in -ing that serves as a present participle and gerund. Most verbs inflect in a simple regular fashion, although there are about 200 irregular verbs; the irregularity in nearly all cases concerns the past tense and past participle forms. The copula verb be has a larger number of different inflected forms, and is highly irregular.
