1. What are Modal Verbs?
Modal verbs are verbs which are used to add meaning to another verb. They follow different grammar rules to regular verbs, and can often be used in many different ways.
The basic modal verbs in English are: can, could, may, might, will, would, shall, should and must.
There are other verbs which behave like modal verbs, although they do not have all the features of ‘full’ modal verbs. Examples include: ought to, need and have to.
2. How are Modal Verbs Different To Normal Verbs?
Modal verbs are different from normal verbs in several ways:
i) Modal verbs can only be used with a verb in the infinitive form, without to:
- I couldn’t sleep last night.
- What should we do?
If you want to use normal verbs with another verb, you need to add a preposition, or change the second verb in some other way:
- She decided to go anyway. —> We need to add the preposition to to use the verbs together.
- I don’t mind doing the shopping. —> We need to change do to doing after mind.
ii) Normal verbs are used in different tenses (past, future, perfect etc.); modal verbs are not.
- She decided to go anyway. —> Past
- She’ll decide next week. —> Future
- She’s already decided what to do. —> Present perfect
Modal verbs don’t have these different forms. Generally, if you use a modal, it can have either a present or a future meaning. Often, we use other words or phrases to show the time.
- It might rain this afternoon. —> We understand that this is in the future only because of this afternoon.
- He could do it if he wanted to. —> Now, or in the future.
There are exceptions: could is used as the past simple of can, and would can have a past meaning in very few situations, but generally modals don’t have past or future forms.
You can sometimes give a modal verb a past meaning by using have + a past participle/3rd form after the modal verb
- He might have overslept. —> We are trying to guess why he is late, and what has happened to him (in the past)
- You shouldn’t have said that. —> You said something rude or inappropriate, and now I’m criticising you for what you did (in the past)
3. Why are Modal Verbs Important?
Modal verbs are used to express many, many different meanings, such as:
- Giving advice: I think you should take the job.
- Talking about possibility: We could do it by Friday, if you wanted.
- Asking permission: May I take this seat?
- Expressing certainty: You can’t have seen him—he’s on holiday in Germany!
And many, many more… All of the meanings which we use modal verbs to express are very, very common in all forms of English. You could hardly say or write anything in English without using modal verbs.
Although modal verbs can appear very simple, they’re actually incredibly complicated, and it will take you time and work to understand them fully.
However, if you can use modal verbs well, this will give you much more control over your English, so it’s worth spending more time to learn about the details of modal verbs.
4. What Makes Modal Verbs Complicated?
In this table, you can see the nine modal verbs on the left, and the nine functions which they commonly express on the right.
Let’s start at the top. We can use can to express:
- Possibility —> It can get really cold in winter here.
- Certainty —> That can’t be a banana—it’s red!
- Asking permission —> Can I borrow your pen?
- Making a request —> Can you help me with something?
- Ability —> She can speak Spanish really well.
Ok, let’s look at the other side. To express possibility, we can use:
- Can —> See example above.
- Could —> We could try to arrive earlier, if that’s easier for you.
- May —> It may be more expensive than you thought.
- Might —> There might be a lot of people there.
Clear? Probably not!
As you can see, each modal verb can express many different meanings, and each meaning can be expressed by many different modal verbs.
Also, in the example above, not all the verbs can be used in exactly the same way. To talk about possibility, may and might are more or less the same, could is similar to may/might but not exactly the same, and can is completely different and cannot be used in the same ways.
Remember, this lesson is not meant to teach you everything about modal verbs. Hopefully, at this point you understand what modal verbs are, how they are different to normal verbs, why they are important for your English, and why they aren’t simple to learn.
This video lesson is part of a series on modal verbs, so check out our other video lessons for more lessons to help you learn about modal verbs in detail.