Auxiliary verbs are essential components in the structure of English sentences, playing a crucial role in shaping the tense, aspect, mood, and voice of the main verbs. They assist in forming various grammatical constructions and are integral to adhering to language rules. Auxiliary verbs, in combination with main verbs, convey different shades of meaning and temporal contexts, thereby enhancing the clarity of communication.
Auxiliary verbs in a nutshell
Auxiliary verbs, or helping verbs, work with main verbs to create different tenses, aspects, moods, and voices. The primary auxiliary verbs are “to be,” “to have,” and “to do.” They form questions, negatives, and various tenses. Modal auxiliary verbs like “can,” “will,” “must,” and “should” express necessity, possibility, permission, and ability.
Definition: Auxiliary verbs
Auxiliary verbs, also known as helping or helper verbs, are verbs that accompany a main verb to help express its tense, mood, voice, or aspect of time. They are essential in forming various sentence structures, including questions, negative forms, and complex verb tenses. Auxiliary verbs autumn into two main categories: primary auxiliary verbs and modal auxiliary verbs. They are both indispensable in English grammar, enabling the construction of complex English verb phrases that convey precise meanings and adhere to specific language rules. The primary auxiliary verbs in their infinitive form are “to be,” “to have,” and “to do,” and are adjusted to the conjugated form, depending on the grammatical moods, tense, aspect, and voice of a sentence.
Note: The negative form of sentences that include auxiliary verbs typically follows this structure:
Auxiliary verb + “not”
Primary auxiliary verbs
- Be – Used to form continuous tenses and passive voice.
- Have – Used to form perfect tenses.
- Do – Used to form questions, negatives, and emphatic statements.
Examples
- She is running. (Present tense)
- The cake was baked by Sara. (Past tense, passive voice)
- The house was being painted last week. (Past continuous tense)
Examples
- We have finished our homework. (Present perfect)
- He had left before I arrived. (Past perfect)
- We have been waiting for the bus since morning. (Present continuous tense)
Examples
- Do you like sushi? (Interrogative sentence)
- I do not know the answer. (Negative sentence)
- She does want to join the trip. (Emphasis)
Modal auxiliary verbs
- Can – Expresses ability or possibility.
- Could – Expresses past ability or polite requests.
- May – Expresses permission or possibility.
- Might – Expresses a weaker possibility.
- Must – Expresses necessity or strong obligation.
- Shall – Expresses future intention or offers.
- Should – Expresses advice or expectation.
- Will – Expresses future intention or willingness.
- Would – Expresses polite requests or hypothetical situations.
Examples
- The children can swim.
- The boy could speak German when he was young.
- The class may be dismissed now.
- It might rain tomorrow afternoon.
- You must always wear a seatbelt.
- Shall we go for a run?
- I should eat more frequently.
- The teacher will help you.
- Would you like a cup of coffee?
Modal auxiliary verbs
Modal auxiliary verbs, often simply called modals or modal verbs, are a type of auxiliary verb used to express necessity, possibility, permission, ability, and other related concepts. Their main distinction from primary auxiliary verbs is that they add meaning to the infinitive verbs in a sentence without changing its form. That said, modal auxiliary verbs are always in their bare infinitive form without the “to.”
For their negative form, modal auxiliary verbs are followed by the word “not.” Modal auxiliary verbs are crucial for expressing a range of meanings and nuances in English, helping to convey the speaker’s intent and the likelihood or necessity of actions and events. Modal verbs can be further categorized into deontic modal verbs and epistemic modal verbs. Implementing these types of modality can help differentiate between necessity and certainty, which are elaborated on in the following.
Deontic modality
Deontic modality conveys necessity, obligation, permission, or prohibition using modal auxiliary verbs. These types of verbs deal with what is allowed, required, or forbidden according to rules, laws, personal duties, and social norms. In essence, deontic modality revolves around the speaker’s attitude toward the desirability or necessity of an action or condition. Common modal auxiliary verbs that are used to express deontic modality are:
- Must (obligation)
- Should (suggestion)
- Can (permission)
- May (formal permission)
- Shall (formal command)
Epistemic modality
Epistemic modality describes the use of modal auxiliary verbs to express the speaker’s judgment about the likelihood, truth, or certainty of a proposition. It deals with the speaker’s assessment of knowledge, belief, or evidence regarding a state or event. In essence, epistemic modality revolves around how certain or uncertain the speaker is about the information that is being conveyed. Common modal auxiliary verbs that are used to express epistemic modality are:
- Must (higher degree of certainty)
- Should (probability)
- Might (low degree of possibility)
- May (stronger degree of possibility)
- Could (theoretical possibility)
Negative sentences
When sentences that include auxiliary verbs are negated, the sentence structure takes on another form. Creating these negative structures generally involves placing the word “not” after auxiliary verbs. The following examples show how auxiliary verbs are used to form negative sentences, adding clarity to communication by indicating what is not the case or what is not allowed, expected, or possible.
Examples
- The girl is not (isn’t) feeling well.
- The players were not (weren’t) told about the change.
- He has not (hasn’t) seen that film.
- The cook had not (hadn’t) peeled the potatoes before he started cooking.
- I do not (don’t) understand the question.
- We did not (didn’t) receive the package.
Examples
- You cannot (can’t) park your car here.
- She could not (couldn’t) believe her eyes.
- It may not rain today.
- They might not join us for dinner.
- We must not (mustn’t) attend the meeting.
- We shall not (shan’t) allow this behaviour.
- You should not (shouldn’t) ignore the warnings.
- I will not (won’t) tolerate this nonsense.
- They would not (wouldn’t) help us.
Interrogative sentences
To form interrogative sentences with auxiliary verbs, the auxiliary verbs are placed at the initial position of the sentence, followed by the subject, main verb, and the question mark. The following examples illustrate how auxiliary verbs are used to create questions about actions, states, permissions, possibilities, obligations, etc.
Examples
- Is the girl feeling well?
- Were the players informed about the change?
- Has he seen that film?
- Had the cook peeled the potatoes before he started cooking?
- Did you understand the question?
- Did they receive the package?
Examples
- Can I park my car here?
- Could you believe your eyes?
- May it rain today?
- Might they join us for dinner?
- Must we attend the event?
- Shall we allow this behaviour?
- Should you ignore the warnings?
- Will you tolerate this nonsense?
- Would they help us?
Examples
Based on the list of auxiliary verbs in the definition section, the following shows basic examples of using these modal auxiliary verbs in different sentence structures.
Can
Examples
- She can swim.
- We can work well together.
- You can do it!
Examples
- You can leave now.
- They can start the process now.
- He can push the button in two minutes.
Examples
- It can be dangerous.
- She can be manipulative.
- They can be poisonous.
Examples
- Can you hand me the pen, please?
- Can he talk any louder?
- Can I present the first part of the presentation?
Examples
- He cannot swim.
- She can’t start the process now.
- Can’t she talk any louder?
Could
Examples
- He could run fast when he was young.
- We could work well together back in the days.
- You could write better in the library.
Examples
- It could rain later.
- She could be manipulative.
- They could be poisonous.
Examples
- Could you pass the salt, please?
- Could you talk a little bit louder?
- Could I start the presentation, please?
Examples
- We could not work well together back in the days.
- He couldn’t swim when he was young.
- Couldn’t you wait a little bit longer?
May
Examples
- You may go home now.
- She may leave the house until dawn.
- We may watch the fireworks from the roof top.
Examples
- She may come to the party.
- It may be sunnier tomorrow.
- They may run late to the party.
Examples
- May I come in?
- May this be the last time?
- May we start the presentation?
Examples
- She may not come to the party.
- You may not attend the meeting.
- They may not arrive to the party on time.
Might
Examples
- We might go out tonight.
- She might arrive earlier than planned.
- I might go for a walk later.
Examples
- You might want to consider another approach.
- She might have to speak to the manager directly.
- I might need to take it into my own hands.
Examples
- Might you be interested in joining for dinner later?
- Might we ask for your opinion on this matter?
- Might they come to the meeting tomorrow?
Examples
- They might not arrive on time for dinner.
- You might not want to bring up that topic in the meeting.
- I might not go to the concert after all.
Must
Examples
- You must wear a helmet while cycling.
- We must finish the report by tomorrow.
- I must wear glasses while driving.
Examples
- She must finish her work.
- They must submit their assignments on time.
- We must follow the company’s code of conduct.
Examples
- They must be at home; their car is parked outside.
- She must be exhausted after working so late.
- The rumors must be true since she hasn’t come to work.
Examples
- You must try this new restaurant; the food is all vegan.
- If you ever visit Paris, you must see the Eiffel Tower.
- We must go to New York during Christmas, it’s supposed to be beautiful.
Examples
- Must we attend the meeting tomorrow?
- Must they follow the same procedures every time?
- Must it always be this difficult to solve these problems?
Examples
- You must not smoke in this building.
- Visitors must not touch the exhibits in the museum.
- We mustn’t try harder in the future.
Shall
Examples
- We shall overcome this issue.
- I shall return home by 7 PM.
- They shall begin the meeting at 10 o’clock.
Examples
- You shall have your money back by the end of the month.
- I shall make sure that everything will be set for the speech.
- They shall have enough time by then.
Examples
- Shall we go out for dinner tonight?
- Shall I open the window for some fresh air?
- Shall we dance?
Examples
- I shall not be attending the meeting tomorrow.
- We shall not leave the house tonight.
- You shall not enter this restricted area.
Should
Examples
- You should see a doctor.
- She should eat more protein to gain muscle.
- They should get a bigger office.
Examples
- The package should be delivered by now.
- The train should arrive in ten minutes.
- He should be here by now; he left an hour ago.
Examples
- Students should complete their homework on time.
- Employees should always wear their ID badges at work.
- She should always wear a uniform to school.
Examples
- We should try the new restaurant around the corner.
- You should watch this film; It’s so interesting.
- We should read the book to get more insights.
Examples
- Should she be home already?
- Should I read these notes before the exam?
- Should they bring anything to the party?
Examples
- You should not be waiting this long.
- I shouldn’t try the dish; I am lactose intolerant.
- Should I not bring the sweet to the event?
Will
Examples
- I will call you back tomorrow.
- She will start her new job on Monday.
- They will visit her grandparents next week.
Examples
- I will help you with your application.
- He will call you as soon as he arrives at work.
- The package will be sent when you receive the confirmation.
Examples
- I will help you.
- We will clean up after the party.
- He will lend you his car if you ask.
Examples
- Will you please pass the butter?
- Will he join us for dinner tonight?
- Will the weather be better tomorrow?
Examples
- I will not pass the test.
- She won’t come to the party in this weather.
- Won’t you sit with me?
Would
Examples
- I would do it if I had the time.
- If he won the lottery, he would travel the world.
- They would move to the city if they found a roof top flat.
Examples
- When he was a kid, he would play outside the whole day.
- Every summer, my family would drive to the sea side.
- Back in the day, we would finish work at 9 PM.
Examples
- She would rather stay at home tonight.
- I would rather travel to South America.
- He would rather scuba dive than snorkel.
Examples
- Would you mind helping me with this task?
- Would he prefer coffee or tea?
- Would it be so bad?
Examples
- I would not count on him.
- They would not be able to make it sooner.
- Wouldn’t it be great, if the sun went down later?
Verb tenses
Auxiliary verbs are essential for forming various verb tenses in English. Helping verbs are used alongside main verbs to create tenses, grammatical voice, mood, and aspect, to help convey when an action occurs, its duration, completion, and other nuances. Aspect in grammar refers to the nature of the action described by the verb, particularly in terms of its completeness, duration, or repetition. The main aspects in English are simple, continuous (progressive), perfect, and perfect continuous. The following sections present an overview of different verb tenses and aspects using auxiliary verbs, along with examples.
Present tenses
Present tenses in English typically entail action verbs that are currently happening, generally true, or habitual states. These tenses include the present simple, present continuous, present perfect, and present perfect continuous. Understanding auxiliary verb constructions in forming these tenses is crucial for mastering English grammar and accurately expressing various time frames and actions.
The present simple tense does not use auxiliary verb constructions for affirmative sentences. However, for the negative from and interrogative mood, it uses the auxiliary verb “to do.”
Examples
- She likes dark chocolate. (Affirmative)
- She does not like dark chocolate. (Negative)
- Does she like dark chocolate? (Interrogative)
The present continuous is a progressive tense used to describe ongoing actions that are currently happening or to refer to temporary actions. It is formed with the auxiliary verb “to be” followed by the present participle form of the main verb.
Examples
- She is eating lunch right now. (Affirmative)
- They are not playing football anymore. (Negative)
- Are you coming to the party? (Interrogative)
The present perfect tense is implemented to describe actions that happened at an unspecified time in the past or an ongoing action that started before now. The auxiliary verb constructions for this tense include “to have” and the past participle form of the main verb.
Examples
- They have finished their homework. (Affirmative)
- I have not visited the new museum. (Negative)
- Has she seen this film? (Interrogative)
As the name already says, the present perfect continuous is also a progressive tense, referring to ongoing actions that started in the past and are still continuing or have recently been completed. This tense is often used to emphasize on the duration of an action. This progressive tense of the present perfect is typically constructed with the auxiliary verb “to have,” followed by “been,” and the present participle of the main verb (verb + -ing).
Examples
- I have been reading this book for two hours. (Affirmative)
- They have not been waiting for long. (Negative)
- Has it been raining all day? (Interrogative)
Past tenses
Past tenses refer to states or actions that happened at some point in the past. There are various types of past tenses with varying auxiliary verb constructions, each with its usage to convey different nuances of past actions. These tenses are crucial for accurately expressing the timing and sequence of past events for effective communication. The main past tenses are the past simple, past continuous (progressive), past perfect, and past perfect continuous.
The past simple is used to describe completed actions or conditions that occurred at a specific time in the past. Affirmative sentences with the past simple do not include an auxiliary verb, but the main verb is in the past tense. The negative and interrogative forms include the auxiliary verb “to do” in its past tense (did) followed by the infinitive form of the main verb.
Examples
- They visited the museum yesterday. (Affirmative)
- He did not (didn’t) go to the party. (Negative)
- Did you see that film? (Interrogative)
The past continuous is a progressive tense that describes ongoing actions that were in progress at a specific time in the past. It is formed with the auxiliary verb “to be” in its conjugated form “was/were,” plus the present participle of the main verb.
Examples
- She was sleeping when the phone rang. (Affirmative)
- I was not eating when you called. (Negative)
- Were they waiting for long? (Interrogative)
The past perfect tense refers to actions that were completed before another action or time in the past. It is constructed with the auxiliary verb “to have” in the past tense, “had,” and the past participle form of the main verb.
Examples
- They had left before we arrived. (Affirmative)
- You had not seen the film before last night. (Negative)
- Had you ever been to Paris before? (Interrogative)
The past perfect continuous tense describes ongoing actions that were in progress up to a certain point in the past, or actions that were ongoing before another past action. It is formed with the auxiliary verb “to have” inflected as “had been” and the present participle of the main verb (+ “-ing”).
Examples
- I had been working there for five years before I moved. (Affirmative)
- She had not been sleeping well before the holiday. (Negative)
- Had he been studying there long when you met him? (Interrogative)
Future tenses
Future tenses play a vital role in indicating actions or conditions that will happen at some point in the future. The modal auxiliary verb “will” is an essential part of constructing future tenses. There are four main future tenses, each conveying different nuances about the timing, duration, and nature of future actions.
The future simple tense is used to convey actions that will happen at a specific point in the future or express a spontaneous prediction or decision. It is formed with the modal auxiliary verb “will” followed by the base form of the main verb.
Examples
- She will travel to Japan next month. (Affirmative)
- I won’t help her with her homework. (Negative)
- Will you help me to clean? (Interrogative)
The future continuous tense describes actions that will be in progress at a specific time in the future. Its structure is formed with the auxiliary verb construction “will be” and the present participle, or “-ing” form, of the main verb, representing the action.
Examples
- I will be waiting for you at the station. (Affirmative)
- They won’t be watching a film tonight. (Negative)
- Will they be joining us for dinner? (Interrogative)
The future perfect tense expresses actions that will have already been completed by a specific point in the future. This tense includes the auxiliary verb construction “will have” in combination with the main verb in its past participle form.
Examples
- She will have finished her work by 5 PM. (Affirmative)
- They won’t have arrived by the time the meeting starts. (Negative)
- Will you have completed the project by then? (Interrogative)
The future perfect continuous is also a progressive tense, conveying actions that will have been in progress for a certain duration by a specific point in the future. It is formed by the auxiliary verb construction “will have been” and the present participle of the main verb, describing the action.
Examples
- By next year, they will have been living here for a decade. (Affirmative)
- They won’t have been studying for three hours by the time you arrive. (Negative)
- Will you have been working here for long? (Interrogative)
Conditional tenses
Conditional tenses are used to describe actions that are dependent on certain conditions. They express hypothetical situations, potential outcomes, and their consequences. There are various types of conditional sentences, each serving different purposes and including different types of verbs and auxiliary verbs.
Present conditional
The present conditional tense, also known as the first conditional, is used to refer to realistic or possible future events that are likely to occur if the condition is met. The structure consists of the word “if,” the modal auxiliary verb “will,” and the base form of the main verb.
Examples
- I will go if it doesn’t rain. (Affirmative)
- If it rains, they won’t join the trip. (Negative)
- Will you help me if I ask? (Interrogative)
Past conditional
The past conditional tense, also known as the second conditional, is used to reflect on past events that did not occur and to imagine different outcomes that could have resulted if those events had occurred differently. This type of conditional tense typically expresses hypothetical alternatives, regret, or critical thinking about past decisions and their outcomes. It is formed with the auxiliary verb construction “would have” and the past participle of the main verb.
Examples
- I would have come if I had known about the party. (Regret)
- If she had applied for the job, she would have been employed. (Hypothetical alternative)
- Would they have succeeded without your help? (Critical thinking)
Use
Apart from tenses and aspects, auxiliary verbs are also an important component in constructing grammatical mood and voice. The mood in grammar conveys the attitude between the narrator and the action verb. In English, there are three main moods:
- Indicative
- Imperative
- Subjunctive
Grammatical voice implies whether the subject of the sentence is performing the action or receiving the action. There are two types of voices in English grammar:
- Active voice
- Passive voice
The upcoming sections delve into how auxiliary verbs contribute to mood and voice in context.
Mood
As mentioned above, the grammatical mood indicates the attitude of the speaker towards the action of the verb. The mood in sentence structures can be distinguished between the indicative mood, imperative mood, and subjunctive mood.
Indicative mood
The indicative mood is used for factual statements, questions, or opinions. It is the most commonly applied mood in English and includes past, present, and future tenses.
Examples
- She is reading a book. (Present continuous, “to be”)
- They have finished their homework. (Present perfect, “to have”)
- Will he go to the market? (Future simple, “will”)
Imperative mood
The imperative mood indicates commands, requests, and instructions. It commonly uses the infinitive form of the main verb and omits the subject in the sentence structure; however, auxiliary verbs are involved in instructions or polite requests.
Examples
- Do your homework, please. (Polite request, “to do”)
- Do not touch that! (Instruction, “to do”)
- Do wash your hands before eating. (Instruction, “to do”)
Subjunctive mood
To express wishes, hypothetical situations, demands, suggestions, or conditions contrary to fact or not necessarily real, the subjunctive mood is applied. It is typically used in formal contexts and can be quite subtle in its use.
Examples
- I wish that he were here. (Wish, “to be”)
- If I were you, I would go. (Hypothetical situation, “to be,” “would”)
- I suggest that he be here by noon. (Suggestion, “to be”)
Voice
In active voice vs. passive voice, auxiliary verbs are integral in English grammar. The choice of voice can change the focus of a sentence from the subject performing the action to the action being executed on the subject.
Active voice
When the subject of the context in a sentence executes the action described by the main verb, the active voice is used. This is the most direct and common way to construct sentences. Here are several examples of the active voice in various verb tenses.
The active voice in combination with the present continuous typically includes the auxiliary verb “to be” in its respective conjugated form.
Examples
- The eldest daughter is writing a letter to her mother.
- The children are taking a break from playing.
An active voice sentence in the present perfect tense is constructed with the primary auxiliary verb “to have” and the main verb in the past participle.
Examples
- The eldest daughter has written a letter to her mother.
- The children have taken regular breaks.
Similar to the present continuous, the past continuous in the active voice is formed with the auxiliary “to be” in the past tense and respective conjugated form.
Examples
- The eldest daughter was writing a letter to her mother.
- The children were taking a break from playing.
The active voice in a past perfect sentence, is built with the auxiliary verb “to have” in the past tense and the past participle of the main verb.
Examples
- The eldest daughter had written a letter to her mother.
- The children had taken a break from playing.
For the simple future tense in the active voice, the auxiliary verbs “will,” “shall,” and “going to” are generally used followed by the infinitive of the main verb to indicate actions that will take place in the future.
Examples
- The eldest daughter will write a letter to her mother.
- The children will take a break from playing.
The active voice in sentences in the future continuous tense is constructed with the auxiliary verb “will,” followed by the word “be,” and the present participle of the main verb.
Examples
- The eldest daughter will be writing a letter to her mother.
- The children will be taking a break from playing.
Passive voice
In the passive voice, the focus shifts from the subject to the action itself or the recipient of the action. In this grammatical voice, the subject is oftentimes left out or added at the end of the sentence, preceded by the word “by.” Below are examples of the passive voice in different tenses.
In the active voice, the simple present does not involve any auxiliary verbs; however, in the passive voice, the auxiliary “to be” is used before the main verb of the action.
Examples
- A letter to the mother is written (by her eldest daughter).
- Regular breaks are taken (by the children).
For the present continuous, the passive voice entails the auxiliary “to be” in the conjugated form “is/are being,” preceding the main action verb.
Examples
- A letter is being written to the mother (by her eldest daughter).
- Regular breaks from playing are being taken (by the children).
A passive voice sentence in the present perfect tense is constructed with the primary auxiliary verb “to have” with the verb “to be” in the past tense before the main verb in the past participle.
Examples
- A letter has been written to the mother (by her eldest daughter).
- Regular breaks from playing have been taken (by the children).
Unlike in the active voice, the passive voice in the simple past tense, uses the auxiliary “to be” in the past tense before the main verb.
Examples
- A letter to the mother was written (by her eldest daughter).
- Regular breaks were taken (by the children).
The passive voice in the past continuous tense uses the auxiliary verb constructions “was being” and “were being” followed by the action verb in the past participle.
Examples
- A letter was being written to the mother (by her eldest daughter).
- Regular breaks from playing were being taken (by the children).
For the past perfect in the passive voice, the auxiliary verb construction “had been” followed by the action verb in the past participle, is used.
Examples
- A letter had been written to the mother (by her eldest daughter).
- Regular breaks from playing had been taken (by the children).
Overview
For a better overview, the following table compares the active voice and passive voice in the various tenses with example sentences.
Examples
| Active voice | Passive voice |
| The chef cooks the meal. | The meal is cooked by the chef. |
| The chef is cooking the meal. | The meal is being cooked by the chef. |
| The chef has cooked the meal. | The meal has been cooked by the chef. |
| The chef cooked the meal. | The meal was cooked by the chef. |
| The chef was cooking the meal. | The meal was being cooked by the chef. |
| The chef had cooked the meal. | The meal had been cooked by the chef. |
Emphasis
Auxiliary verbs also have the special role of adding emphasis to a statement, particularly with the verb “to do” and its conjugated forms. This type of emphasis can be used to affirm something strongly, correct a misconception, or express surprise or insistence. The auxiliary verb “do/does/did” is placed before the main verb for emphasis, making statements more forceful and clearer. For the third-person singular, you use the conjugated form “does,” while the first and second-person singular, as well as the plural forms, use “do.” In sentences with the past tenses, you used the conjugated form “did.” Here is how to use auxiliary verbs for emphasis.
Examples
- I do like your idea for the approach.
- He does need to finish the project on time.
- She did know all about the subject.
Examples
Person A: You don’t seem to care about our grade.
Person B: I do care about our grade!
Person A: She doesn’t seem to enjoy the sport.
Person B: She does enjoy playing sports.
Person A: You didn’t do your chores.
Person B: I did do my chores!
Examples
- You do need to be careful with that.
- She does have to keep up the pace.
- They did arrive early, just like they promised.
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FAQs
Auxiliary verbs are helping verbs that are used alongside main verbs to construct different tenses, aspects, moods, and voices, and to add emphasis. Therefore, auxiliary verbs are essential for forming accurate and meaningful sentences.
The main auxiliary verbs, also called primary auxiliary verbs, are “to do,” “to have,” and “to be,” in their respective conjugated form.
Here is a list of verbs that indicate modality:
- Can
- Could
- May
- Might
- Must
- Shall
- Should
- Will
- Would
Here are examples sentences for each auxiliary verb:
- I was running a lot faster yesterday.
- He has finished his assignment.
- They did not come to the party.
- I will call you when I arrive at the airport.
In an auxiliary verb construction, we typically find an auxiliary verb in combination with a main verb in various conjugated forms, depending on tense, mood, voice, aspect, and modality.
