Modal verbs – a handy summary
Modal verbs are often troublesome to many students. First of all, you must rememeber that all but ought & have require no preposition with the following verb. Secondly, as it is true for modal verbs, they do not need any operators to create questions or negative statements. Although we have a small number of modal verbs they can express multiple states and intentions. Below I present almost all possible meanings they can bear in sencences. In my research for a good grammar explanation of modal verbs usage I found a perfect summary in Grammarway by Jenny Dooley and Virginia Evans. It is still available on Amazon. Just click the picture.
At some time of your English education you must have come across one of the books attributed to these English gurus. The following theory was organized in the order they propose, but the examples are mine.
Below the article you will find a link to an interactive exercise on modal verbs. You can also download this exercise in .pdf format to print out and do at home.
Here is the list of meanings of any modal verbs you might use:
Ability can be expressed with:
Mary can play the piano. (She is able to play this kind of instrument.)
I can bring the money tomorrow morning. (I will manage to do that tomorrow morning.)
Mary could play the piano when she was 6. (She was able to play this kind of instrument at the age of 6.)
I could bring the money yesterday, so I did it. (I managed to do that yesterday.)
When we are obliged to do something we can express it with:
She must practise playing the piano everyday. (It is her duty to practise that everyday. Her piano teacher told her to practise everyday.)
We must leave early. (We have no time to stay longer. We have other duties to perform.)
- have (got) to
We have got to be at the station at 8.15a.m. (If we are not there till 8.15 we will miss the train)
She will have to retake the exam next year. (She failed in the exam and it is required from her to take it again next year. It can be an exam which she is obliged to take every year.)
- should / ought to
We should save water. (It is necessary to save water to protect environment and save natural resources.)
We ought to participate in this training. (This training is useful. It will help us in our work.)
absence of necessity
When there is no need to do something we can use:
- needn’t do
We needn’t do this exercise. (It’s not necessary. Our teacher did not tell us to do it.)
- needn’t have done
We needn’t have booked the hotel. (It wasn’t necessary but we did it. Someone else had booked it for us before or the hotel had planty of rooms available so advance booking was not necessary.)
When we want somebody not to do sth or something is forbidden in general we can use the following expressions:
You mustn’t go outside after 9p.m. (It’s forbidden for you because either you are too young to go outside late either it is not safe for you to go outside and safety precautions do not allow you to leave your place.)
You can’t speed up in this area. (It is forbidden by law to speed up. It could be dangerous for you and the pedestrians. You must adhere to the speed limit there.)
When we assume something basing on logic we can express it with:
- must (in possitive assumptions)
They are wearing wellingtons. It must be raining. (Otherwise they wouldn’t be wearing such boots.)
They knew every detail of our plan. We must have a mole in the office. (There is no other possibility to get know about our secret.)
- can’t / couldn’t (in negative assumptions)
They knew about our next move. They couldn’t just guess it. (It is impossible just to guess that. I’m sure about that.)
probability & possibility
When something is likely to be true or likely to happen we use:
- should / ought to
Sally was supposed to attend the meeting. She ought to be at the meeting now. (I saw her colleagues going to the conference room where the meeting takes place – so it’s probable.)
We have more options to express general possibility:
The store can get overcrowded. (There is such a general possibility.)
- could / may / might (when sth is possible in a specific situation)
The store could/may/might get overcrowded tomorrow because it will be Black Friday. (It usually gets overcrowded that day. We can expect many customers to come for the sales we will have that day.)
Could/Might/may the store get overcrowded tomorrow? (We do not use may in questions when we want to express possibility.)
- could / might have been (when something was possible to be done/to happen but it wasn’t done, didn’t happen)
I left my car unlocked yesterday. It might have been stolen, but luckily it wasn’t.
There are different modal verbs we can use to talk about permissions, but the usage of each differs depending on the type of a sentence. When we ask for a permission (questions) we have the following options to choose from:
- can / could / may / might
Can I borrow your pen?
May I see the menager, please?
Might we enter the conference room now? (very formal and rarely met)
- can / may (when giving permission)
You can borrow my pen.
You may enter the room.
We do not use could and might when giving permission because it would mean something different then. Could and might imply that there is some condition to meet before you are allowed to do something.
- can’t / mustn’t / may not (when refusing permission)
I’m sorry but you can’t use this phone.
Customers may not enter this area.
Could I stay outside a little longer? No, you can’t.
In the examples above we do not use couldn’t and might not for the same reason as before: they would imply that on some condition it would be possible.
- can / be allowed to (when talking about permission)
All citizens over 18 can vote.
I was allowed to smoke in the office.
Modal verbs serve this purpose perfectly. Whenever we want to make a request they are indispensable. A simple please is always welcome, of course. The less formal requests can be expressed by:
Can/will you get me a glass of water, please?
Will you clean up your room at last?
More formal (and more polite) requests are created with:
Would/could you open the door for me, please?
In a typical situation in a shop or a restaurant, when we want to have/order something we use:
Can/Could/May I have this dessert, please?
- Shall [I/we] do sth (used only with 1st person in Singular or Plural)
Shall we go to the cinema tomorrow? (Why don’t we go to the cinema? How about going to the cinema? Let’s go to the cinema.)
Where shall I put these flowers? (Where do you want me to put these flowers? Where do you suggest I put these flowers?)
- [subject] can/could
The assembly department can hire additional personnel. (It might help to mitigate the problem of increased workload.)
We could go to the theatre instead. (Why don’t we go to the theatre instead? Let’s go to the theatre instead.)
- Should / ought to
You should go home as soon as possible. It’s getting dark. (It’s advisable to go home. Otherwise, you will have to walk in darkness. You had better go home now.)
Modal verbs in this function are usually used to express that something was advisable to do but it wasn’t done or something was not advisable to do but it was done. The Perfect form of the verb used after modals suggests that the action/condition was already done and we don’t like it.
- should/ought to have done sth
You should have asked me before you took the whole pie. (but you didn’t ask me)
You shouldn’t have left the door unlocked. (but you did leave it unlocked)
You can find here a simple matching exercise on modal verbs. It contains typical modal verbs with their corresponding meaning expressed with other verbs and expressions. You can also dowload this exercise in .pdf file from the download manager.