English conjugation, Auxiliaries and Modals verbs | Conjugator Reverso

Auxiliary and modal verbs

Auxiliary verbs, or helping verbs, are usually used together with a main verb to add extra meaning to a sentence. They can also be used to conjugate verbs in compound tenses, to ask and answer yes-no questions or to express negation and the passive voice.

A: “Do you like singing?” B: “Yes, I do!” (to like)
B: “Can I borrow your laptop?” B: “No, you can’t!” (to borrow)

Be, do and have

The three most common auxiliary verbs, “be”, “have” and “do”, are called primary auxiliaries.

Like ordinary verbs, they have both infinitive and irregular conjugated forms. They can sometimes be used alone as main verbs, e.g. “He does just as I say” (to do), “I had everything I needed” (to have), “We have never been to England” (to be).

As an auxiliary, “be” is mainly used for continuous forms, e.g. “I am learning English” (to learn) and for the passive voice, e.g. “She was raised by her mother” (to raise).

“Have” is also used as an auxiliary to form compound tenses such as the present or the past perfect, both in the active and the passive voice. E.g. “Have you tried to call him?” (to try), “He had been given a second chance” (to give).

“Have” is the only auxiliary that can be used with modal verbs to talk about possible past events, e.g. “He may have been right but we will never know for good.” (to be)

“Do” is used as an auxiliary to form questions and negative sentences with ordinary verbs. In the spoken negative form, “not” is contracted and changes to “-n’t”, e.g. “Did you see that? – No, I did not / didn’t!” (to see). “Do” can also be used for emphasis with ordinary verbs, e.g. “Stop calling me lazy, I did clean the bathroom!” (to clean)

Modal verbs

Modal verbs are a special type of auxiliary verbs. They are always followed by the infinitive of a main verb without “to”, e.g. “You can leave now” (to leave), “She might know about this already” (to know).

They have only one form and cannot be conjugated with other auxiliaries (no continuous tenses or passive forms): you cannot say “she musts”, “I am mighting” or “you were coulded”. Negatives are formed by adding “not” after the modal verb. Some modals can be contracted: “can’t”, “couldn’t”, “wouldn’t”, “shouldn’t”, “won’t” and “shan’t”.

Two modals can be used as past forms of others: can (present) could (past) and will (present, future) would (past).

“I think I can do this” “I thought I could do this”
“I know someone will help me” “I knew someone would help me”
“Need (to)”, “ought (to)”, “dare (to)” and “used to” are semi-modal verbs: like modals, they can sometimes be combined with main infinitives to create new verbal expressions.
Both “can” and “will” function as regular verbs in certain contexts, e.g. “Berries can be made into jam, frozen or cannedat home” (to can) and “I willed myself to sleep but it wouldn’t come” (to will).
All modals are auxiliary verbs, but not all auxiliary verbs are modals!
Example of modal verbs use