Introduction
When learning a language on our own, it's usual to have questions that we find difficult to answer, but with a little research, nothing is impossible. As their name suggests, auxiliary verbs are essentially terms that go with the main verb in a sentence to aid in its conjugation in the appropriate tense or grammatical mode for the communication context. Auxiliary verbs can be used in all tenses and modes, but they also assist us indicate whether we are using the active or passive voice. The auxiliary verb is a verbal form specialized in providing grammatical information, mainly tense, aspect and manner, but also person, number and voice. The auxiliary verb is combined with auxiliary verbs, responsible for the categorical selection of the set, as well as providing the semantic content of the construction.
Task
A. Complete with the correct form of the auxiliary verbs do, be or have the following sentences:
- They _______ playing tennis with some friends of mine.
- I _______ know what to watch on TV last night.
- Where _______ you want to go?
- In spite of being a vegetarian, she ______ like cucumbers.
- The students have _______ reading this book for weeks.
- _______ you cooking when your wife came in?
- ________ worry, I ______ getting better.
- This movie _______ being very interesting. I am about to leave the cinema.
B. Fill in the blanks with the correct modal verb: will, would, should, ought, shall, must, might, may, could, can.
- You ________ win the next championship.
- _______ you meet with me on Friday?
- If you want to pass the exam, you _______study harder.
- _______ you like to play tennis with me?
- You _______ wear a seatbelt.
- It __________ rain this evening.
Process

Main points
- The auxiliary verbs be, have and do are used to form the negative and interrogative structures of the verbs.
- The auxiliary be is used for continuous forms and the passive voice.
- The auxiliary have is used for the perfect forms.
- The auxiliary do is used to build the negative and interrogative structures of sentences that have a verb in simple form.
How do I identify it?
The auxiliary verb is a verb that is used as a way to form the mood, tense, and voice of other verbs within a sentence.
Auxiliary verbs are used very often in any situation. We list the most common uses of the verb to be, do and have.
1. Ask questions
The auxiliary verbs will help us to ask questions in English since it is necessary to conjugate at the beginning of these the verb to do for sentences in the past, the verb to be in the present or the verb will in the future.
2. Form negative sentences
You need to conjugate the auxiliary verb to do to form the negation in English.
3. Compound tenses
You will find the auxiliary verb to have in compound tenses such as the present perfect or the past perfect.
4. Passive voice
In the passive voice you will always find the conjugated verb to be accompanied by a main verb in the past participle.
5. Form the conditional
In the English conditional you need to use auxiliary verbs. For example, in the second conditional, you will find two auxiliary verbs, the verb to be and the verbs would or could.
Evaluation
A verbal form specialized in providing grammatical information will be evaluated, fundamentally, tense, aspect and manner, but also person, number and voice. The auxiliary verbs are in charge of helping the sentence to be coherent with the tenses and grammatical persons; Also, it allows people to understand the meaning of the dialogue. In short, without them English would be a mess; but given the auxiliary verbs, this is not so. Since, these have the job of facilitating reading and learning.
Conclusion
In conclusion, auxiliary verbs are, in simple words, the verbs that we use to form different tenses such as the past or future, as well as different structures such as negative and interrogative sentences.
Likewise, these auxiliary verbs fulfill the important function of supporting, helping or adding relevant details about the main verb of a sentence.