What is copula? How to use in English

The word "copula" is derived from Latin, specifically the Latin word "copulāre," which means "to join together" or "to connect." The term was first used in logic and philosophy by the medieval scholar John Duns Scotus in the 14th century to refer to a word or expression that links a subject and a predicate in a sentence, forming a statement. This central verb or linking word is what's known as a copula, such as "is," "are," or "was" in English. This usage of copula became common in grammatical discussions during the 18th century and has been a part of modern linguistics and grammar ever since. It's now used to describe the part of speech that links grammatical subjects to predicates, helping to create sentences and express ideas.