Were is the past tense of be.(verb)
An example of were is what a student would say if he was telling his mother that he and his friends had studied yesterday.
See were in Webster's New World College Dictionary
See were in American Heritage Dictionary 4
Origin: Middle English were, weren
Origin: , from Old English wǣre, wǣren, wǣron; see wes-1 in Indo-European roots. Our Living Language Although many irregular verbs in English once had different singular and plural forms in the past tense, only one still does today—be, which uses the form was with singular subjects and the form were with plural subjects, as well as with singular you. The relative simplicity in the forms of most verbs reflects the long-standing tendency of English speakers to make irregular verbs more regular by reducing the number of forms used with different persons, numbers, and tenses. Since past be is so irregular, speakers of different vernacular dialects have regularized it in several ways. In the United States, most vernacular speakers regularize past be by using was with all subjects, whether singular or plural. This pattern is most common in Southern-based dialects, particularly African American Vernacular English (AAVE). Some speakers use were with both singular and plural subjects; thus, one may hear she were alongside we were. However, this usage has been much less widespread than the use of was with plural subjects and appears to be fading. • In some scattered regions in the South, particularly in coastal areas of North Carolina, Virginia, and Maryland, vernacular speakers may regularize past be as was in positive contexts and regularize it as weren't in negative contexts, as in He was a good man, weren't he? or They sure was nice people, weren't they? At first glance, the was/weren't pattern appears to come from England, where it is fairly commonplace. However, in-depth study of the was/weren't pattern in coastal North Carolina indicates that it may have developed independently, for it is found to a greater extent in the speech of younger speakers than in that of older coastal residents. • Other forms of negative past be include warn't, common in American folk speech in the 18th and 19th centuries, and wont, as in It wont me or They wont home. Wont, which often sounds just like the contraction won't, historically has been concentrated in New England and is also found in scattered areas of the South.
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