Lesson 19. Modal Verbs

Grammar Focus: Modal Verbs

Modal verbs are special helping verbs. They add meanings such as ability, possibility, permission, obligation, advice, certainty, prediction, or willingness to another verb.

Common modal verbs include:

can, could, may, might, must, shall, should, will, would

How Modal Verbs Work

Most modal verbs follow the same basic pattern:

subject + modal verb + base form of the verb

Important Rules

Modal verbs are different from ordinary verbs in several ways.

• Do not add an s in the third-person. Example: He can swim.
• Do not use do or does when making questions. Example: Can you help me?
• For the negative form, put not after the modal verb. Example: I should not go.
• Do not use to after a modal verb. Example: She must leave.
• They do not have an infinitive form.
• They do not have all the forms of ordinary verbs.

The following sections will discuss each of the modal verbs.

Can

The modal verb can is very common and means either to have the ability to do something or to have permission to do something.

1. Ability

We use can to say that someone has the ability to do something.

Form:

subject + can + base verb

Examples	Français
I can speak English.	Je peux parler anglais.
She can swim across the lake.	Elle peut nager à travers le lac.

Questions

To form a question, put the subject of the sentence after can.

Examples	Français
Can she swim?	Peut-elle nager ?
Can you speak English?	Parlez-vous anglais ?

Negative

To form a negative statement, use cannot or its common contraction can't.

Examples	Français
She cannot swim.	Elle ne sait pas nager.
I can't drive.	Je ne sais pas conduire.

2. Permission

Can is also used to ask for or give permission.

Examples	Français
Can I open the window?	Puis-je ouvrir la fenêtre ?
You can leave early today.	Vous pouvez partir tôt aujourd’hui.

Could

The modal verb could has several important meanings.

1. Past Ability

Could is the simple past of can and is used for general abilities in the past.

Examples	Français
She could swim across the lake before she broke her leg.	Elle pouvait nager à travers le lac avant de se casser la jambe.
I could swim when I was five.	Je pouvais nager quand j’avais cinq ans.
She could speak French when she was a child.	Elle pouvait parler français quand elle était enfant.

2. Possibility

Could is used to say that something is possible.

Examples	Français
She could swim across the lake if she wanted to.	Elle pourrait nager à travers le lac si elle le voulait.
It could rain tomorrow.	Il pourrait pleuvoir demain.
We could miss the train.	Nous pourrions manquer le train.

3. Polite Requests

Could is used very often to make polite requests.

Examples	Français
Could you help me?	Pourriez-vous m’aider ?
Could you open the door?	Pourriez-vous ouvrir la porte ?

4. Hypothetical Situations

Could is also used to talk about an ability or possibility that depends on one or more conditions.

Examples	Français
I could help you if I had more time.	Je pourrais vous aider si j’avais plus de temps.
We could go to the beach if the weather improved.	Nous pourrions aller à la plage si le temps s’améliorait.

Could Have

Could have + past participle is used to talk about a possibility or opportunity in the past. Could have is often shortened to could've.

Examples	Français
She could have won the race.	Elle aurait pu gagner la course.
We could have gone to the concert.	Nous aurions pu aller au concert.
Could she have swum across the lake?	Aurait-elle pu nager à travers le lac ?
She could've swum across the lake if she'd wanted to.	Elle aurait pu nager à travers le lac si elle avait voulu.
She could have taken the earlier train.	Elle aurait pu prendre le train plus tôt.
They could have forgotten about the meeting.	Ils auraient pu oublier la réunion.

Forms of Can / Be Able

Unlike most verbs Can only has a present and a past tense. For other forms, be able is used. The following table shows the different forms that are used.

May

Possibility

May and might are both commonly used when something is possible but uncertain.

Examples	Français
John may have an extra pen.	John a peut-être un stylo de rechange.
I may go to the concert.	Je pourrais aller au concert.
I may not have time to eat dinner.	Je pourrais ne pas avoir le temps de dîner.
She may be able to help you.	Elle pourrait être en mesure de vous aider.
It might happen.	Ça pourrait arriver.
I might not be able to do it.	Je pourrais ne pas être en mesure de le faire.

Permission

May can also be used to ask for or give permission, especially in more formal situations. In informal situations, can is more commonly used to ask for or give permission.

Examples	Français
May I go to the store?	Puis-je aller au magasin ?
May I have something to drink?	Puis-je avoir quelque chose à boire ?
You may have one chocolate bar.	Vous pouvez avoir une barre de chocolat.

May Have and Might Have

May have + past participle and might have + past participle are both used to indicate that an event possibly happened in the past. Might have is often shortened to might've.

Examples	Français
It might have happened.	Ça aurait pu arriver.
I may have lost the keys.	J’ai peut-être perdu les clés.

Must and Have to

1. Obligation

Must and have to can both express strong obligation.

Examples	Français
You must wear a seat belt.	Vous devez porter une ceinture de sécurité.
I have to work tomorrow.	Je dois travailler demain.
She has to pass the exam.	Elle doit réussir l’examen.
She must pass the exam, or she will fail the course.	Elle doit réussir l’examen, sinon elle échouera au cours.

Must is only used in the present tense. Have to is especially useful because it can change form for different grammatical contexts.

Form	Expression
Infinitive	to have to
Present	must / have to
Past	had to
Present perfect	have had to
Past perfect	had had to
Conditional	would have to
Future	will have to

Examples	Français
She had to leave early.	Elle a dû partir tôt.
I'll have to do it eventually.	Je devrai le faire un jour ou l’autre.
She had to pass the exam to be able to pass the course.	Elle a dû réussir l’examen pour pouvoir valider le cours.

2. Must for Strong Deductions

Must does not always express obligation. It can also express a strong conclusion based on what we know or observe.

3. Must Not and Don't Have To

Must not and don't have to have very different meanings.

Examples	Français
We've been walking for two hours. We must be near the lake.	Nous marchons depuis deux heures. Nous devons être près du lac.
He must be almost at the lake by now.	Il doit être presque au lac maintenant.
I must be going too slow.	Je dois marcher trop lentement.

Must Not = Prohibition

Use must not or mustn't when an action is not allowed or it is very important not to do something.

Examples	Français
You mustn't leave.	Vous ne devez pas partir.
You mustn't bring food into the library.	Vous ne devez pas apporter de nourriture à la bibliothèque.
We must not forget to lock the door when we leave.	Nous ne devons pas oublier de fermer la porte quand nous partons.

Don't Have To = No Necessity

Use don't have to when something is not necessary. You can do it, but you are not required to do it.

Examples	Français
You don't have to leave.	Vous n’avez pas à partir.
I don't have to bring my laptop.	Je n’ai pas à apporter mon ordinateur portable.

Must Have

Use must have + past participle to make a strong deduction about the past.

Examples	Français
I must have left my keys at home.	Je dois avoir laissé mes clés à la maison.
They must have known what would happen if they did that.	Ils doivent avoir su ce qui arriverait s’ils faisaient ça.
He must've forgotten about it.	Il doit l’avoir oublié.

Should

1. Advice and Recommendations

We commonly use should to give advice or make recommendations.

Use should + base verb. Do not use to after should.

Examples	Français
You should get more exercise.	Vous devriez faire plus d’exercice.
You should study more.	Vous devriez étudier davantage.
We should see the new film.	Nous devrions aller voir le nouveau film.

2. Asking for Advice

To ask for advice, put should before the subject.

should + subject + base verb?

Examples	Français
Should I study tonight?	Est-ce que je devrais étudier ce soir ?
What should I do?	Que devrais-je faire ?
Should we leave now?	Est-ce qu’on devrait partir maintenant ?

3. Negative Form: Shouldn't

Use should not or the contraction shouldn't to advise someone not to do something.

Examples	Français
You shouldn't worry.	Vous ne devriez pas vous inquiéter.
You shouldn't drive so fast.	Vous ne devriez pas conduire si vite.
We shouldn't spend so much money.	Nous ne devrions pas dépenser autant d’argent.

4. Expectations

Should can also express an expectation. In this use, we are saying that we think something will probably happen or that we expect a situation to be true.

Examples	Français
The train should arrive soon.	Le train devrait arriver bientôt.
They should be home by now.	Ils devraient être à la maison maintenant.
The package should arrive tomorrow.	Le colis devrait arriver demain.

5. Ought To

Ought to has a meaning similar to should, especially when giving advice or talking about what is appropriate.

Examples	Français
You ought to get more sleep.	Vous devriez dormir plus.
We ought to help them.	Nous devrions les aider.

For most everyday situations, you can use should.

Shall

In everyday English, shall is most useful in questions with I and we. We commonly use it to make suggestions and offers.

Like other modal verbs, shall is followed by the base form of the verb without to.

1. Making Suggestions

Use shall we + base verb? to suggest doing something together.

Examples	Français
Shall we go?	Allons-nous ?
Shall we start?	Allons-nous commencer ?
Shall we eat outside?	Allons-nous manger dehors ?
Shall we invite Marta?	Allons-nous inviter Marta ?

2. Making Offers

Use shall I + base verb? when you offer to do something for someone or ask whether they want you to do something.

Examples	Français
Shall I open the window?	Je devrais ouvrir la fenêtre ?
Shall I help you?	Je devrais vous aider ?

Note: Can I ... and Would you like me to ... are both more common ways to offer to help someone.

Will

Will + base verb is one of the most common ways to talk about the future. It expresses predictions, promises, spontaneous decisions, and things we believe will happen.

The common contraction of will after a subject is 'll.

1. Predictions and Future Events

Use will when you predict or expect something to happen in the future. Will often pairs with adverbs of probability like probably, definitely, certainly, or maybe.

Examples	Français
We will talk about it later.	Nous en parlerons plus tard.
I'm sure it will work.	Je suis sûr que ça va marcher.
He will probably arrive soon.	Il arrivera probablement bientôt.
We'll have time for dinner.	Nous aurons le temps de dîner.

2. Spontaneous Decisions

Use will when deciding something at the moment of speaking.

Examples	Français
I'll get the door.	Je vais ouvrir la porte.
I'll call you tomorrow.	Je vous appellerai demain.
That sounds good. I'll come!	Ça a l’air bien. Je viendrai !

Offers and Promises

Will is often used when making a promise, offer, or commitment to someone.

Examples	Français
I will help you with your homework.	Je vous aiderai avec vos devoirs.
We'll take care of everything.	Nous allons tout régler.

Negative Form

The negative form is will not, which is commonly contracted to won't.

Examples	Français
We won't have time for dinner.	Nous n’aurons pas le temps pour le dîner.
It won't work.	Ça ne marchera pas.
They won't finish on time.	Ils n’arriveront pas à temps.

Questions

To form a question, put the subject of the sentence after will.

Examples	Français
Will you go shopping after work?	Allez-vous faire des courses après le travail ?
Will they come tomorrow?	Vont-ils venir demain ?
What will you do?	Que ferez-vous ?

Would

Would has several important uses. The two most common are hypothetical situations and polite requests.

1. Hypothetical Situations

Use would when talking about imaginary or unlikely situations. This is often paired with an if-clause.

Would is often contracted to 'd

Examples	Français
I'd go to the concert if I had more money.	J’irais au concert si j’avais plus d’argent.
We would buy the house if it were cheaper.	Nous achèterions la maison si elle était moins chère.
She would travel more if she had vacation time.	Elle voyagerait plus si elle avait du temps de vacances.
She'd help us if she could.	Elle nous aiderait si elle le pouvait.
They would help if they knew the truth.	Ils nous aideraient s’ils connaissaient la vérité.
I'd learn Italian if I lived in Rome.	J’apprendrais l’italien si je vivais à Rome.

2. Polite Requests

Would is also common in polite requests.

Examples	Français
Would you help me?	M’aideriez-vous ?
Would you open the window, please?	Ouvririez-vous la fenêtre, s’il vous plaît ?

Past Habits

Would can also describe repeated habits or actions that happened in the past but do not happen now. It has the same meaning as used to.

Examples	Français
When I was young, I would play outside every day.	Quand j’étais jeune, je jouais dehors tous les jours.
We would visit them every summer.	Nous les rendions visite chaque été.

Negative Form

Would not is usually contracted to wouldn't.

Examples	Français
I wouldn't do that.	Je ne ferais pas ça.
They wouldn't agree.	Ils n’accepteraient pas.