Modal verbs can be tricky, especially when it comes to using them in a sentence. However, once you learn how they work, they are extremely easy to use. In the following article we explain everything you need to know to use modal verbs with ease, as we teach in our English courses.
What are modal verbs?
Modals (also called modal verbs, modal auxiliary verbs, modal auxiliaries) are special verbs that behave irregularly in the English language. These are different verbs from those we commonly use such as “work, play or visit”, among others. They give additional information about the function of the main verb that follows and have a wide variety of communicative functions.
How to use modal verbs in a sentence
The great thing about modal verbs is that they all follow three simple rules for making affirmative, negative and interrogative sentences. Let’s take a closer look:
- Affirmative sentences:
Affirmative sentences are the same for all subjects with modal verbs, which means that it is not necessary to add -s to the third person singular.
He must study today. He must study today.
- Negative sentences:
To formulate negative sentences, we only need to add the particle “not” between the subject and the verb.
They cannot study today. They cannot study today.
- Interrogative sentences:
To ask questions, we simply reverse the subject and modal verb:
Will you go? Will you go?
What are modal verbs used for?
Probability
Some things seem likely, but we do not know for sure. In these cases, you can use the modal verbs should and must to show probability without certainty.
- Her parents must be so proud. His parents must be very proud.
Possibility
In situations where something is possible but not certain, use the modal verbs could, may or might.
- She may become the youngest pro soccer player ever. She may become the youngest female professional soccer player in history.
Ability
The modal verb can shows whether the subject is capable of doing something, such as performing an action or demonstrating a skill. Likewise, the negative form, can or can’t, shows that the subject is unable to do something.
- He can speak three languages, but none of them well. He can speak three languages, but none of them well.
Ask for permission
If you want to ask permission to do something, start your question with can, may or could. Traditionally, in the most formal and polite use, may is best for permission. However, in modern usage may and can are both perfectly acceptable options when describing the possibility or permission.
- May I leave early today? Can I leave early today?
Request
Similarly, if you want to ask someone else to do something, start your question with will, would, can or could.
- Will you turn that music down? Do you want to download that music?
Suggestion/advice
What if you want to recommend something, but not order? If you are giving suggestions or advice without giving orders to someone, you can use the modal verb should.
- You should try the lasagna. You should try the lasagna.
Order
On the other hand, if you want to order someone to do something, use the modal verbs must, have to or need to.
- You need to be here before 8:00. You need to be here before 8:00.
Obligation or necessity
Modal verbs can express a necessary action, such as an obligation, duty or requirement. Likewise, the negative form expresses that an action is not necessary. Use the same modal verbs as with commands: must, have to or need to.
- You don’t need to come if you don’t want to. You don’t have to come if you don’t want to.
Habit
To show a continuous or habitual action-something the subject does regularly-the modal verb would can be used for the past tense and will for the present and future. The phrase used to is also acceptable if it is a habit that no longer exists.
- I will arrive early and leave late to every meeting. I will arrive early and leave late for all meetings.
As you can see, modal verbs are essential for many functions in English. Now that you have seen how to use them, try to put them into practice when speaking and writing.
