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Concourse 2

Teaching Modal auxiliary verbs

modal There are four language analysis guides that you should have done / do / be familiar with before you tackle this one:
    A general guide to modal auxiliary verbs
    A guide to modal auxiliary verbs one by one
    A guide to semi-modal auxiliary verbs
    A guide to types of modality


Other languages

The concept of modality is common to all languages.  We all have a need to express things like willingness, probability, likelihood, obligation, requirement and so on.  Modality may not only be achieved by the use of modal auxiliary verbs, of course.  Saying something like:
    I'm almost certain he'll be late
instead of
    He'll be late
is still using modality in language.
Modal auxiliary verbs are, however, very variable across languages.  Here's a brief run-down by major language groupings explaining a little of how it all works.  There won't be enough detail here for your particular students and your setting but it is somewhere to start.  You can get more on line but beware the unreliability of many sites.
Swan and Smith, 2001, is a usually reliable source albeit frustratingly inconsistent in covering modality.

Languages What they do
Standard Arabic does not have modal auxiliary verbs which correspond exactly to English modal auxiliaries.
However, it does have many precise and detailed ways to express modal concepts.  For example
must, have to, should, might, may, it is possible to, it is impossible to, it is expected that, it is easy to, it is hard to, it's worth mentioning that, it's well-established that, it's most likely that, it's forbidden to, it's permitted to, it's more proper to
and a range of other concepts are all expressed through a form of modal construction.
The problem, of course, is that these categories do not mirror the modal categories of English so expect a good deal of confusion, especially with modal auxiliary verbs like may and could which have a range of functions.
The concept of having a large range of modality in the language will not be mysterious to learners from an Arabic background.
(Source: Arabic learning resources at http://arabic.desert-sky.net/g_modals.html)
Chinese languages Modern Standard Chinese, too, has a range of modal auxiliary verbs, as one would expect of an isolating language.  They are, however, not at all parallel to those in English.  There are, for example, three modal auxiliary verbs which perform the functions associated with can (ability, permission, possibility) in English.  The most commonly used modal auxiliaries in Chinese languages express
want; ask for; wish; desire
want to; would like to; feel like (something)
should; ought to; must
can; be able to; be capable of
like; love; prefer; enjoy; be fond of
can; may
be good at; be skilful in
be willing to

Conceptually, modality poses no problems but overlapping meanings will make life difficult.
(Source: Modal auxiliary verbs at http://www.sunrisemethod.com/pages/45/Modal_verbs_19)
Slavonic languages including Russian, Polish, Ukrainian, Czech, Slovak etc. Slavonic languages also have modal auxiliary verbs but, as usual, the categories don't exactly match (although they are closer than many languages).  A single verb form (roughly translatable as must) serves in Polish for the English verbs must, need to and ought to, for example.
In Czech, there is a clear distinction between externally and internally imposed obligations, often rendered in English by must vs. have to, should or ought to.
Russian has a simpler modal system than English so you may encounter, e.g., He must not used to mean He needn't / doesn't have to.
(More on Polish at http://www.polish-dictionary.com/polish-modal-verbs)
Germanic languages These languages use modality is ways quite similar to English which makes life easier for learners from these language backgrounds.  The most important exceptions often concern the negative uses.  For example, in German the translation of needn't / don't have to, expressing the lack of obligation either way, would be must not [muss nicht] and that causes confusion.  To translate the English sense of must not meaning prohibition, German uses a different modal auxiliary verb [darf nicht], roughly translatable as may not.
In Swedish, the verb used for the sense of needn't is cognate with the English expression behove.
In these languages, too, there are usually more tense forms available so an equivalent of had to may be rendered as '*musted'.  Learners may be confused by a logically constructed tense form in their first language, the past or future of must, for example, not existing in English.
The overlap in meanings between cognate modal auxiliary verbs is not precise so expect errors such as It can be used to mean It might be.
There are few serious conceptual difficulties otherwise.
Italic languages including French, Spanish, Italian, Portuguese, Romanian etc. These languages do not have a separate grammatical category for modal auxiliary verbs and usually render the concepts as a verb followed by an infinitive form, e.g., in French Je peux aller (I can go) or in Spanish Puedo ir.  Expect, therefore, errors such as
    *I can to eat
    *You must to enter
etc. because many learners perceive the to-form as the infinitive in English.
Some modal concepts, e.g., for obligation, are expressed in the passive (It is necessary that ...).
Swedish, Danish and Norwegian Scandinavian languages have a separate class of modal auxiliary verbs although use is an issue.  The verb kan, for example, is used to talk about the possible future where English would use may or might.  Expect, therefore,
    *It can rain tomorrow.
Other uses of modal auxiliaries are close parallels with English.
Japanese Japanese has two classes of modal auxiliary verbs: those which are attached to stems and cannot function independently and those which are ordinary verbs which lose their meanings when acting as auxiliaries.  We have, therefore, structures such as miru (to see) leading to mirareru (to be able to see).
The concept of modality will not be strange but the form will cause problems in English.
Other languages Some languages have a very reduced set of modal auxiliary verbs to call on.  Greek, e.g., really has only two (must and can), one of which only exists in the It is necessary / necessarily true that sense in the third person.  Added to these problems is the tendency to make past modal auxiliary verbs in completely different ways (often rendering the modal auxiliary in the present with the main verb in the past) so mistakes such as
    *I can saw it (for I was able to see it)
are possible.
Turkish speakers will have few problems with the modal system of English as such because the language has many parallel structures.


General problems for all learners

Whatever you students' first language(s), there are certain aspects of the English modal system which will cause problems:

  1. Form and function
    If you have followed the analysis guides in the area, you will be alert to the issue that in English one verb can perform a range of functions.  The modal could, for example, is used to express:
    present possibility That could be the postman now. epistemic modality
    future possibility It could rain tomorrow. epistemic modality
    past possibility He could have seen her.  I'm not sure. epistemic modality
    present ability I could help with that, if you like. dynamic modality
    future ability I could finish in hour if I get some peace. dynamic modality
    past ability When I was only two, I could swim pretty well. dynamic modality
    permission Could I ask you a question? deontic modality
    complaint You could have warned me! dynamic modality
    This works both ways.  Permission, for example, can be realised using may, might, can, could etc.
    For more, got to the guide to modal auxiliary verbs one by one.
  2. The modal system in English exhibits a range of anomalies.  For example, the negative of
        It must be him
    used for deduction is
        It can't be him
        It mustn't be him
    There are numerous other cases of non-parallel structures.
  3. Modal auxiliary verbs are often contracted and, in natural speech, often rendered with weak-form vowels.  So we get must pronounced as /məs/ and can as /kən/ or even /kn/ etc. as well as needn't've or couldn't've etc. which are hard to perceive and even harder to produce.
  4. Few languages have verb forms analogous to English semi-modal auxiliaries (dare, need, used to) and the forms will be difficult to master.


Approaches to teaching modal auxiliary verbs

Fundamentally, there are two ways to approach the teaching of modal auxiliary verbs (and all modality expressions for that matter):

  1. Form first: take each modal auxiliary verb as a separate entity and present its various functions logically and appropriately, considering the level of the learners
    For example:
    Consider the modal auxiliary verb can and then teach the functions of:
        I can swim
        It can get cold in the winter here
        You can't be serious
        He can't have missed the train again

    and so on.
  2. Function first: decide on the type of modality you want to tackle and then select the modal auxiliary verbs which express the function appropriately, considering the level of the learners
    For example:
        Obligation: teach must, have to, should, ought to, had better etc. according to level and previous learning
        Ability: teach can, could, be able to, could have, was able to etc. according to level and previous learning
        Possibility: teach might, could, must, can't have, couldn't have, will etc. according to level and previous learning
    and so on.

To illustrate, you can conceive the relationship in these two ways:

Approach 1

Approach 2

approach approach

If some of the terms are unfamiliar to you, follow guide to types of modality or simply ignore them.  The following will still make sense.

Each has advantages and drawbacks.

  • If you take Approach 1:
    • you risk encouraging your learners to think that there is a one-to-one relationship between the verbs and their functions
    • you are going from form to function rather than function to form and that's not how the mind operates
    • it will be reassuring because this is the way many courses are structured and many coursebooks written so it's familiar to both learners and teachers
    • it allows for bite-sized lessons focusing on a single use of a single verb
  • If you take Approach 2:
    • you need to make intelligent decisions regarding which and how many verbs to present for each type of modal function
    • you may find it difficult to fit the approach within a school syllabus because that is not how they are usually constructed
    • you will be moving from function to form and that fits with how the mind operates in this area
    • you will be giving your learners an appropriate range of ways to realise the functions they need to communicate

Some people may take, of course, Approach 1 at lower levels and move to Approach 2 when the learners have succeeded in mastering a range of simple modal auxiliary verbs expressing a limited range of functions.
Whichever route you choose, the considerations which follow are applicable.


Teaching modal auxiliary verbs

To master any modal-verb use we need to know two things:

  • the speaker/writer's perception of reality
    If a speaker chooses to say
        It'll rain
    rather than
        It might well rain
    the intention (arising from the speaker's view of the future) is subtly different
  • the context in which it is used
    It is impossible to interpret something like
        I could leave earlier
    without knowing the context.  It can mean
        I was given permission to leave earlier
        I was able to leave earlier
        I may
    (in future) leave earlier
    We need to supply a good deal of information for learners to be able to interpret the sentence accurately:
    • How is the event situated in time (future or past)?
    • What is the speaker's relationship in terms of authority with others?
    • Is the speaker likely to be talking about ability or permission, given the preceding text?

For example, the statement
    She must write to her mother
has a number of possible interpretations.  What are they and how does the hearer unpack the meaning?  Click here when you have an answer.


Handling other issues

  1. The one-form-many-functions and one-function-many-forms problems need careful handling.  It is unwise to try to teach any modal in isolation.  What we need to do is to focus on particular functions of the form independently.  Trying to teach may in contexts where it means both possibility and permission:
        It may rain
        May I ask a question?
    is a recipe for disaster.  We have seen above that many languages will reserve separate structures for these functions.
    A much better approach is to focus on the concepts of types of modality and teach, say, may for epistemic modality:
        That may be true
    separately from may for deontic modality:
        You may not leave yet
    This way, logical constructs will not be confused.  If terms like epistemic and deontic are new to you, follow the guide to types of modality.
  2. Anomalous forms such as the difference between must not and don't have to / needn't also need careful handling in context.  The context must make it clear what sort of obligation (if any) is present.
    Equally, modal auxiliary verbs of deduction must be presented in a way that makes it clear what sort of deduction can be made with what level of certainty.  Here's an example of something commonly used.  What are the problems?
    must have etc.
    Click here when you have detected the two problems with exercises like this.
  3. We need to provide lots of targeted listening and production practice in the weak and contracted forms of modal auxiliary verbs.  Drilling is one way but getting learners to select from a multiple-choice list whether they heard, e.g., must've, mustn't've, could've, couldn't've etc. embedded in natural-speed utterances is another way to prepare them for listening in 'the real world'.
  4. Semi-modal forms are increasingly rarely produced as pure modal auxiliary verbs.  For example, dared not is usually now didn't dare, didn't used to is preferred to usedn't to and so on.  We need to ask ourselves whether at most levels it is wise to introduce the modal forms at all (except where they may occur and then only for comprehension).  This means de-selecting texts which contain them.
    The subtle difference between needn't have and didn't need to is another issue we could leave well alone until learners are really competent in using modal auxiliary verbs.


Degrees of likelihood (epistemic modality)

This is an area which deeply confuses many learners for a number of reasons:

  1. Because many languages have only one modal to talk about probability and use adverbials to increase / lessen the sense of how probable something is.
  2. Because English uses at least 4 separate modal auxiliary verbs to express probability: might, may, could and can.  It also uses will, incidentally in, e.g.:
        That will be the postman at the door
  3. Because it is often taught in a confusing manner providing false, or at least questionable, information.

There is a school of thought which attempts to represent degrees of probability along some kind of cline from, say, 10% probability up to 90% probability and then arrange the modal auxiliary verbs on the cline so we get something like:

0% ← ← ← ← ← probability → → → → → 100%
can't could may might must

This is actually misinformation and only serves to confuse the learner, primarily because it isn't true. When you have thought about why this is the case, click here.

The general rule is that these modal auxiliaries do not represent different levels of uncertainty or probability in themselves.  What matters are all the other signals in the text or in the speaker’s tone and or gesture / expression.  In fact, they can all vary between 1% and 99%.  Both might and could are used almost interchangeably in English although in plain written text there are those who say might sounds more improbable.  That is arguable.  The verb may is almost always more formal.


Genre approaches to teaching modal auxiliary verbs

If you have followed the guide to genre, you will aware that certain text types will use modality in very different ways.
When we teach modal auxiliary verbs, especially to learners who need to write conventional texts, it is worth bearing this in mind.

  • Instructions sometimes employ deontic or alethic modal uses such as must:
    often in passives:
        the flame must not be allowed to touch the oil
    or as imperatives:
        do not over tighten the screw
  • Discussion texts (arguing both sides of a case) will often contain 'hedging' modal auxiliary verbs:
    epistemically: in expressions such as:
        It might be argued that ...
    or dynamically: in formulations like:
        One could consider ...
  • Recounts and Narratives may employ modal auxiliary verbs:
    epistemically for speculation and deduction as well as possibility:
        I don't know what I must have been thinking
        I must have been mad
        It couldn't have been worse
        I can't tell you
    and dynamically:
        I wasn't able to catch the train
        I couldn't get to the station in time
  • Information reports contain very little modality normally because they don't usually deal with possibilities and so on, confining themselves to facts.
    When modality is employed, it is often alethic:
        The eggs must be incubated for 20 days
        The solution has to be heated to 150 °C
  • Explanations often involve modal auxiliary verbs:
    epistemically of possibility: can cause ... , may result in ... etc.
    or dynamically of ability / willingness: can't break, won't be airtight etc.
  • Expositions (arguing one side of a case) employ
    deontic modality to make a case: should be, cannot be, must be, ought to be etc.
    and epistemic modality to appear certain: this will surely result in ..., that must lead to ... etc.

In writing lessons, in particular, it is useful to focus on modality because a genre approach, by its nature, points learners towards noticing how the intention of the writer is realised in the use of language structure.

Other guides to do with modality are:

Related guides:
essential guide to modality a simpler guide in the initial training section
pure modal auxiliary verbs a traditional view taking each modal in turn and identifying its function
semi-modal auxiliary verbs which also considers marginal modal auxiliary verbs such as seem, tend, be about to etc.
time, tense and aspect the place to go if the distinctions between, e.g., perfect and perfective, continuous and progressive are obscure
complex tenses which also considers complex tenses in relation to modality
modality: tense and aspect which considers modal auxiliary verbs and perfect and progressive forms and also has some teaching ideas
types of modality For more on types of modality mentioned here: epistemic, deontic, dynamic and alethic
functions index modal auxiliary verbs play an important part in expressing many other functions such as expressing (un)certainty, obligation etc.
hedging and modality for a guide to how these concepts are used in English for Academic Purposes
The modality map for more choices

Campbell, GL, 1995, Concise Compendium of the World's Languages, London: Routledge
Swan, M and Smith, B (Eds), 2001, Learner English, 2nd Edition, Cambridge: Cambridge University Press