What is a Copula?
A copula is a special type of verb in English, though in other languages other parts of speech may serve the role of copula. A copula acts as a connector between the subject of the sentence and some sort of modifier. Because of this role, in English a copula is often also referred to as a linking verb.
The shining example of the copula in English, and many other languages, is the verb to be, which most often serves to link the subject of the sentence with the predicate -- a part of the sentence which modifies the subject. Some examples of this use of to be include:
Can anything ever be enough?
The house is on top of the hill.
Jets are fast.
Notice how in each of these sentences, the verb to be is not being used in the literal verbal sense, meaning 'to exist', but is rather taking the second part of the sentence -- the predicate -- and using it to modify the first part.
By contrast, in the sentence: I think, therefore I am. the verb is not a copula, but rather a full verb literally indicating existence. This duality that most copula verbs have can often cause confusion when people attempt to refine their speech to be more grammatically standard. Most of us learn early on that we must use adverbs to modify verbs, and adjectives to modify nouns. This is why when we use the sentence: I ran over here as fast as I could. our English teachers or resident grammar mavens may correct us, noting that the word we should use is quickly, since ran is a verb, and fast is an adjective.
The problem comes when people attempt to generalize this rule to copula verbs. The trick being that adverbs should be used to modify action verbs but that does not include all verbs. The verb to feel for example, may be used as an action verb, but may also be used as a copula verb. A common over-correction is in response to the question, How do you feel? with the incorrect response: I feel badly.
In this case, the speaker uses the adverbial form badly rather than the adjectival form bad since they recognize feel as a verb. In this context, however, feel is used as a copula verb, not an action verb, and so the adjectival form is correct. By using the modifier badly, it is implied that feel is being used as an action verb, with the meaning of the sentence rendered to something like, My tactile senses function quite poorly. What is meant, of course, is to modify the I with the copula, saying something like, Bad is an apt way to describe the state I am in.
One interesting quirk of copula verbs in Indo-European languages is that they tend to be far more irregular than any other verbs in the language. The poster-child copula, to be for example, has eight distinct forms -- in contrast to the four or five forms other verbs typically have. Added to the eight forms -- be, being, been, is, am, are, was, and were -- historically there were an additional four forms -- best, art, wast, and wert -- giving the verb more than double the forms of regular verbs.
Written by Brendan McGuigan
