logo ELT Concourse teacher training: The Bridge

The Bridge: Modality


On your initial training course, you encountered something called modal auxiliary verbs (quite likely rather loosely described as modal verbs or simply, and sloppily, as modals) and may have spent some time identifying the nature of these special verbs in English and considering the sorts of things they do.
This is not the place to itemise modal auxiliary verbs and identify what they imply.
This is the stuff of, for example:

and so on.

Central modal auxiliary verbs

These are sometimes called pure modal auxiliary verbs.

? To remind yourself of the main meanings of some central or pure modal auxiliary verbs, try a short matching test.

You probably got all of that right.  If you didn't, it's time to review the initial plus guide to the essentials of modality, linked below.

? The next thing to do is to remind yourself of how to identify central modal auxiliary verbs.  There are some tests and you should be able to remember them before you click here.

That was another fairly easy test but do not be concerned if you didn't identify all the rules or categorised them differently.

Semi-modal auxiliary verbs

Semi-modal auxiliary verbs:

  1. Sometimes take the forms of central modal auxiliaries
  2. Sometimes work as modal auxiliary verbs but do not follow the structural rules for central modal auxiliary verbs
  3. Sometimes operate as 'normal' lexical verbs.

The usual list of semi-modal auxiliary verbs includes just three: need, dare and used (to).  To that list some will add ought (to) and let.

For more on this, see the guide linked below to semi- and marginal modal auxiliary verbs.

? Try a short test to see if you can identify when a verb is acting as a central modal auxiliary verb, a semi-modal auxiliary or a 'normal' lexical verb.  Click here to do the little test.

Now that you have got the basics in your mind, it's time to take a slightly different view of modal auxiliary verbs and see if there's a better way to categorise them for teaching purposes.
There is, of course.


Four kinds of modality in English

We can tell our students that a verb is expressing ability or obligation or permission and so on in any given clause and that can be a helpful short-hand way of analysing something.  It can also confuse because some verbs will fall into more than one category.
For example, what do:
    John should be here
    She may go
Click here when you have an answer.

So, in order to teach modality in a way that makes intuitive sense, we need overarching categories into which to set the verbs, whether they are modal or semi-modal in nature.

Here they are:


Deontic modality

This form of modality concerns obligation, lack of obligation, advice and permission.  It comes from a Greek word meaning duty.

A number of verbs can express this concept, for example:

and so on.


Epistemic modality

Epistemic modality concerns the speaker / writer's view of the likelihood or possibility of a proposition being true or untrue.
Again, we have a range of possible forms to do this, for example:

and so on


Dynamic modality

This refers to ability or willingness and we only use two verbs modal auxiliary verbs to do this: can/could and will/would.  For example:

false true

Alethic modality

This refers to absolute truths both positive and negative and there are no degrees of those.  So, for example, the following express alethic modality:


Overlapping and ambiguity

There is in this area, as in many others in language analysis, something called categorical indeterminacy.  This means that it is sometimes not an easy matter to attribute some language items to a single category.
This is either because there is no context or co-text or because even with a context the items can carry two possible meanings.
There is overlap both in the type of modality an utterance may express and the kind of modality we should assign to a particular utterance.
Some examples will help:

This underlines the need to present all modal language with a clear context and a clear co-text.  Sentence-level analysis is not good enough.


Modality without modal auxiliary verbs

One problem with language analysis on most initial training courses is inevitable.  The need to cover a range of types of language in a short course with other competing priorities often results in half truths being presented because they are neat and brief.
However, later in any teacher's career, the need becomes apparent to refine and deepen understanding.
This is especially true of modality where the temptation is to confine the phenomenon to modal auxiliary verbs of one kind or another and ignore all the other ways there are to express the four types of modality we have just encountered.
Here are some examples of modal meaning expressed without modal auxiliary verbs:

  1. epistemic modality
    1. Verbs:
          That proves he is at home
          This contradicts the idea that it is going to be easy
          That undermines my faith in her honesty
    2. Nouns:
          There's a good chance he's in
          That's an impossibility
          This is evidence of theft
    3. Adverbs:
          She's obviously intelligent
          That's arguably true
          He's patently got it wrong
    4. Adjectives:
          It's an undeniable effect of the weather
          She's a possible replacement
          That's a debatable position
  2. deontic modality
    1. Verbs:
          She is compelled to work late
          They encouraged me to sing a song
          I was allowed to decline
    2. Nouns:
          I don't feel an obligation to go
          It's your duty to pay for the work
          There's no need for you to complain
    3. Adverbs:
          She's necessarily strict
          He was needlessly rude
          That was pointlessly detailed
    4. Adjectives:
          This is an obligatory declaration
          She's liable for the costs
          That's a needless complication
  3. dynamic modality
    1. Verbs:
          I achieved the targets
          They managed to do it
          He coped with the workload
    2. Nouns:
          It was a great success
          That was a terrible failure
          Her accomplishment was recognised
    3. Adverbs:
          It was unproductively done
          That was fruitlessly discussed
          The problem was effectively solved
    4. Adjectives:
          It was a fruitless attempt
          There was a pointless argument
          This was a successful project
  4. alethic modality
    1. Verbs
          Parallel lines do not meet
          A triangle is not permitted to have more than three sides
          A polysyllabic word needs more than one syllable
    2. Nouns:
          It is a fact that a polygon has many sides
          The truth is that the sun is just another star
          A prerequisite of a window is transparency
    3. Adverbs:
          A trio is necessarily made up of three people
          It is always important to protect the terminal from water
          It will inevitably melt
    4. Adjectives:
          A required characteristic of an isosceles triangle is two equal sides.
          The inescapable truth is that I am 60 years old
          It is unavoidable that the work cannot be finished

Some of these alternatives may sound somewhat unnatural, especially in the areas of dynamic and alethic modality, because English happens to be rich in modal auxiliary verbs performing the same modal functions, but the admonition always to use modal auxiliary verbs to perform these functions is mistaken and unhelpful.
Other languages, which may have a more limited range of modal auxiliary verbs, often confined to expressions for must, can and should, will use more of these non-modal-auxiliary ways of expressing the same ideas and learners from those language backgrounds may often select something in English which expresses the right meaning but is either clumsy or too formal.

? Finally, to see if you can identify the four types of modality, try a test.

If that's all clear enough to you, you can go on to the guides below (on the right).  If you still feel slightly confused, try the links on the left.


Guides in other areas
Initial plus essential guides In-service guides
the essentials of modality semi- and marginal modal auxiliary verbs
central modal auxiliary verbs (more difficult) modality without modal auxiliary verbs
auxiliary verbs the in-service modality map