Modal verbs in English loom large as an area for study. They can be categorised in terms of function, intensity and meaning. Modals can be confusing as individual verbs can be used in many different ways.
The best way to tackle these verbs is to split them up into batches and learn the different usages of these groups of verbs.
Let’s begin with a definition.
What is a modal verb? – a modal verb is a type of auxiliary verb, they can be used to express a certain functions such as possibility, necessity, ability etc.. or make an utterance more polite or tactful.
How are sentences with modal verbs constructed? – the modal verb is the first verb in the verb phrase and is followed by the infinitive (without to) of the main verb.
- People may (modal verb ‘may’) arrive (main verb – infinitive without ‘to’) late because of the snow.
can, could, may, might, shall, should, will would, must, dare, be able to, ought to, need to, have to
Try this Gapfillers exercise on mixed modals to see if you can choose the correct one in each sentence.
In this first post on Modal verbs we will look at the following functions and explore which verbs can be used and how they differ.
Ability – being able to do something
Can is used to describe ability and can’t/cannot the lack of ability.
- Joe can help us with this problem but Paula can’t.
We can also use able to
- Joe is able to help us with this. (there is a sense of surprise or confirmation when using this form).
NB: don’t use able to with the passive
For the future, present perfect, past, gerunds and infinitives we use be able to –
- They will be able to fix the pipes.
- I wasn’t able to visit them over Christmas.
- I haven’t been able to get out of the house since Tuesday.
- I like being able to arrange my own timetable.
Unable to – is used for absence of ability in formal situations – We regret that we are unable to agree to your terms.
Could is used for possessing an ability in the past and in questions, and sentences with adverbs such as hardly or only
- She could speak before she was a year old.
- Could the doctor see you?
- I could only see the nurse.
Other uses of could for ability are:
- inability – Even though he was a vet he couldn’t cure his dog.
- missed opportunity – We could have visited them but we didn’t have enough time.
- disappointment – You could have told me that they had divorced!
Prediction – making statements about what will happen in the future
Will and won’t are used for prediction in the present tense:
- You should take warm clothes – it will be cold in December.
- Maisie won’t be home yet she doesn’t finish work until 6.00.
Would is used for the past:
- We always knew they would marry eventually!
Must, should and have (got) to can also be used for prediction.
- That must be Stephen’s brother. (deduced from information you have)
- That has got to be Stephen’s brother! (He looks just like him)
- We shouldn’t have a problem recognising Stephen. (We have a very good description)
Can, can’t, could, may and might are usually used for expressing permission or absence thereof. There are degrees of politeness inherent in the choice of verb.
- Can I borrow your pen? – Yes, you can/Sorry, I’m afraid you can’t, I’m using it.
- Could I borrow your pen? (more polite) (answer with can/may or can’t)
- May I borrow your pen? (more formal) (answer with may/can’t)
- Might I borrow your pen? (very formal – perhaps the person is a stranger) (answer as before)
Deduction – drawing a conclusions
Can, could, may, might, must, have (got) to, should
- Take sandwiches as food can be very expensive on the train.
- A temperature could be a sign of something more serious.
- The trains may be running late with all this snow.
- That might be Jasper he said he would call.
- He must be on his way.
- He has got to be at least fifty years old now.
- We should all get decent bonuses this year judging by the company results.
Remember this is a quick summary to help you test your knowledge of the rules and how to apply them. It is worth checking for more detailed information in your grammar book. (see my post on choosing dictionaries and grammar books)
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