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Concourse 2

Expressing certainty and uncertainty

I beseech you, in the bowels of Christ, think it possible that you may be mistaken.
(Oliver Cromwell to the synod of the Church of Scotland on August 5 1650)

cromwellthink

Expressing certainty and uncertainty is a key communicative language skill and needed by learners at all levels of competence.  Hedging and vague language are allied concepts so they are also dealt with here.

There are times when we don't want to state things definitely and clearly.  What are the possible reasons for that?  Think for a moment and then click here.

Downplaying certainty is called hedging.

Here are some examples of what this guide is about.
Can you spot:

  1. The parts of the following in which the speakers / writers are being sure or being vague or uncertain?
  2. The way they are doing it – i.e., the linguistic realisation of certainty, hedging and vagueness?

When you have an answer to a. and b. above, click on the eye open to reveal some comment.

She seems to be upset.
eye open
  1. She seems to be upset.
  2. The use of copular verbs such as seem, appear, looks (like) etc. is a common strategy.
He tends to be rather rude.
I assume John will be late.
eye open
  1. He tends to be rather rude.
    I assume John will be late.
  2. The use of so-called introductory verbs such as tend, assume, believe, suggest and so on is another common strategy.  The use of tend, in particular, is very common indeed and rarely taught.  In British English it takes the place of expressing current or past habit (would / used to) as a way of sounding less certain.  Compare:
    We used to have lunch on the terrace.
    We tended to have lunch on the terrace.
    We don't go to the cinema much.
    We tend not to go to the cinema much.
That'll be the postman.
That might be them now.
That could be the case.
eye open
  1. That'll be the postman.
    That might be them now.
    That could be the case.
  2. Modal verbs are used frequently to express various levels of certainty.  How certain the speaker sounds is often dependent on stress and intonation rather than the intrinsic concept of the modal itself.  Compare, e.g.,
    That must be him. ↓
    (falling intonation)
    That must be him.
    ↑ (rising intonation)
    You could be right. ↓
    (falling intonation)
    You could be right. ↑
    (rising intonation)
I'll certainly try.
He'll probably be late.
You are conceivably wrong.
eye open
  1. I'll certainly try.
    He'll probably be late.
    You are conceivably wrong.
  2. These are modal adverbs (acting as adjuncts) and there are plenty of them in English which imply various levels of certainty, doubt and likelihood.
    Fronting the adverbs has a major effect.  Compare, e.g.,
    Probably, we'll get it done.
    We'll probably get it done.
    Clearly, you are wrong.
    You are clearly wrong.
I often think he's a bit too clever.
I sometimes feel he's deliberately unpleasant.
eye open
  1. I often think he's a bit too clever.
    I sometimes feel he's deliberately unpleasant.
  2. Here two things are happening:
    1. The speaker is using a projecting mental process verb.  There are lots of these including believe, feel, guess, consider etc.
    2. The speaker is making the comment less definite by the use of time adverbs, specifically frequency, here.  Other examples include (in)frequently, seldom, usually etc.
He is certain to be there.
It is possible it will be too expensive.
There are sure signs of improvement.
eye open
  1. He is certain to be there.
    It is possible it will be too expensive.
    There are sure signs of improvement.
  2. Modal adjectives like these are used in a similar way to modal adverbs.  They express both certainty (sure, certain etc.) and uncertainty (possible, probable, conceivable etc.) and are frequently used with existential It and There sentences.
There's a strongish possibility that he won't come.
There an outside chance that he will arrive on time.
There's a reasonable likelihood that she'll be late.
eye open
  1. There's a strongish possibility that he won't come.
    There an outside chance that he will arrive on time.
    There's a reasonable likelihood that she'll be late.
  2. Modal nouns like these are almost always qualified in some way with an adjective which either makes them more or less certain.  Collocation is an issue because one can have a strong possibility but a weak possibility is at least unusual.  Similarly, outside chance is the antonym of good chance (not bad chance).
    Note, too, that we frequently use the -ish suffix in spoken English to downplay the adjective modifier.
That's going to be a bit hard to do.
He's inclined to be a tad sure of himself.
That's a little too much.
There are a few new ideas here.
eye open
  1. That's going to be a bit hard to do.
    He's inclined to be a tad sure of himself.
    That's a little too much.
    There are a few new ideas here.
  2. These are vague quantifiers or partitives (more below) and are very common in softening the directness of what is said.  Learners of English rarely use them effectively.
    Note, by the way, that in the second example, the speaker combines the vague quantifier with an introductory verb, inclined to.  That's quite common.

More detail and exemplification follows.


modality

Modality

Expressing uncertainty or certainty using modal expressions (not just modal auxiliary verbs) is referred to as epistemic modality.  The term comes from the Greek word for knowledge (ἐπιστήμη, epistēmē).  We are expressing our view of the truth of a proposition on a scale of 0% possibility to absolute certainty.

Examples above of modal verbs doing this job are:
That'll be the postman.
That might be them now.
That could be the case.

pure

pure modal verbs

A number of pure or central modal verbs can function to express epistemic modality.  They do this in three ways:

  Positive Negative
Expressing the possibility that something is true It can be cold here in February It can't be raining again
I could be delayed by the weather He couldn't have got lost
He may be late He may not come on time
That might be the postman at the door That might not be what you imagine
Expressing the logical necessity that something is true (not always with absolute certainty) That letter must be from the bank It can't be from your mother
It couldn't be from your mother
If it's at Platform 5, it should be the London train If it's at Platform 5, it shouldn't be the one we want
She ought to be at home by now That's oughtn't to be our train.  It's on the wrong platform
Expressing a prediction that something will be true That will be the 6:30 bus That won't be him ringing.  It's too early.
That would be the warmest place to sit That wouldn't be a very comfortable bed.
Because John is such a bad player, I shall beat him easily Because he plays well, I shan't beat him easily.

Notes:

  • ought to is often considered a semi-modal verb and is, in fact, the only one that can be used to express epistemic modality (dare, used and need cannot be used this way).  The negative use of ought to is rare.
  • shall is quite rare, even in BrE
  • an alternative to must in this sense is have (got) to (e.g., in That has to be the right bus) but there is no negative, can't and couldn't being preferred.  The insertion of got strengthens the sense of certainty.
marging

marginal modal verbs

(For a bit more, see the guide to semi- and marginal modal expressions)

A few of these can express some sense of epistemic modality.

seem to
That seems to be the train we need
tend to
The train tends to be busy on Fridays
be likely to
That's likely to be a busy restaurant
be supposed to
He's supposed to be the manager
possible

modal adverbs, adjectives and nouns

modal adverbs
There were examples of these above using certainly, probably, clearly etc.
Other examples are:
admittedly
assuredly
avowedly
certainly
clearly
decidedly
definitely
evidently
incontestably
incontrovertibly
indeed
indisputably
indubitably
inevitably
manifestly
maybe
necessarily
obviously
of course
patently
perhaps
plainly
probably
really
surely
unarguably
unavoidably
undeniably
undoubtedly
unquestionably
As in, e.g., That is indisputably false / plainly correct / undeniably possible / decidedly unlikely etc.
modal adjectives
There were examples above to which we can add
absolute
certain
clear
complete
definite
likely
possible
potential
probable
total
unlikely
These adjectives modify modal and other nouns as in, e.g.
There's a clear chance / a possible issue / a total impossibility / a definite opportunity / a potential problem etc.
modal nouns
There were examples above using possibility, chance and likelihood to which we can add opportunity and certainty but almost no others.  As was noted, these are almost always (but not always) modified in some way as in e.g.
There's a complete certainty / outside likelihood / definite opportunity etc.
finite

finite clauses

As we saw with the examples using tend and assume, a number of verbs in finite clauses can be used to express epistemic modality.  Many of these verbs act as copular forms and include but are not confined to:

  • They suspected she was the thief
  • I assume he's coming
  • We think it's going to be OK
  • It appears to be the part we want
  • I imagine it'll be late
  • I guess he's her brother

blurry

Vague language

In addition to all of the above, English has a number of ways to express vagueness.  For example, we can say Thirty people came to the party or we can hedge our bets and say something like Around thirty came or Near enough thirty people came etc.  Here are examples of vague language.  Can you classify them?
Click here when you have a mental list of three categories.

  1. I want to get some eggs, milk and other breakfast stuff.
  2. There are seats for up to twenty people here.
  3. Pass me the thingy on the left.
  4. It's got a certain je ne sais quoi about it.
  5. I don't want to get people into rows and the like.
  6. There are over twenty of them.

apple

Teaching this area

This is an area at which learners of the language tend to fall into two camps: those who preface all remarks with Perhaps or Maybe and sound overly tentative and unsure and those who fail to use the language of uncertainty effectively to soften what they say.  It therefore demands our attention.

As we saw above, the area is complex and there is a range of ways to express certainty and uncertainty and to hedge.  We can, if we are not careful, overwhelm our learners so the area needs to be approached piecemeal, one or two structures at a time.

raising awareness

A simple approach is to start with recognition of the speaker's level of certainty.  Like this:

  1. For modal auxiliary verbs:
    Put a tick in the right box.
    Statement Sure Maybe Very unsure
    That will be the postman at the door.      
    That could be the postman at the door.      
    That might be the postman at the door.      
  2. For verbs:
    Statement Sure Maybe Very unsure
    I assume he's coming.      
    I know he's coming.      
    I think he's coming.      
    I suspect he's coming.      
  3. For adverbs:
    Statement Sure Maybe Very unsure
    He's probably here already.      
    He's certainly here already.      
    He's possibly here already.      
    He's definitely here already.      

The same kind of approach can, clearly, be taken for the other strategies in the table above.

For vague language we can take similar awareness-raising approaches.  For example,

  1. For quantities
    Statement 20-70 40-60 49-51
    Around 50.      
    Nearly 50.      
    Less than 65.      
    Over 40.      
  2. For placeholders
      Round Object Green Grasshopper Circle Sticker
    The glass thingy.      
    The green whatsitsname.      
    The round doobrie.      
  3. For list completions
    Which endings are possible? other stuff done. some other people. lots of other stuff. some other things done.
    I need to get some shopping and        
    He brought his friends and        
    She got her hair and        
    They used my car and        

noticing

Almost all texts and dialogues (if they are reasonably authentic) will contain examples.  Advertising is a particularly rich source.  For example:

  1. What are you actually getting?
    Up to 20% off!  Over 50 in every packet!  More than 20 different uses!
  2. Highlighting examples helps at first to get people alert to the types of language.
    I had a great birthday party.  All my friends from Uni and Margate came and the family were there, too, as well as some other people I didn't know.  There might have been as many as forty of us but certainly more than 30.  We had planned on food for up to 25 but knew there was a good chance we'd have to get a bit more in.  I didn't see your brother but it's perfectly possible he was there, isn't it?  After all, he usually doesn't miss a good opportunity for free food so I assume he was there.  It seems everyone else was!

practising

  1. Rephrasing is helpful.  For example:
    Over fifty but not as many as 60 can be rephrased as: at least fifty
    It's an object whose name I don't know for opening tins can be rephrased as: the thingy to open tins
    I am only 20% sure he is here can be rephrased as: he might be here
    I am almost sure it is possible can be rephrased as: it should be possible
  2. Varying the expressions to see what effect it has is also helpful.  For example:
    All my friends from Uni and Margate came and the family were there, too, as well as some other people I didn't know / some others / a few mates.  There might have been more than / as many as / over / nearly forty of us but certainly fewer than 50 / more than 30 / over 25 / not more than 60.  We had planned on food for up to / nearly / almost / approximately 25 but knew there was some chance / a good chance / a strong possibility / a fair likelihood we'd have to get lots / a bit / some more in.  I didn't see your brother but it's perfectly possible / there's a reasonable chance / there's an outside chance he was there.  After all, he rarely / never / barely ever misses a good opportunity / easy chance / for free food so I assume / guess / imagine / get the feeling he might have been / could have been / must have been there.  It seems / is certain that / appears / is clear that everyone else was!
  3. Using realia in lessons can be productive if you are sure that the class don't know the proper words for them.  That means they are forced into using placeholders to refer to them.  Commercial catalogues are a good source of pictures if you can't lay your hands on the objects.
  4. Another practice routine is to ask for opinions in areas where people have very little experience.  For example,
    How do you think the Inuit spend the summers?
    What would you do on holiday in Guatemala?
    Where would you buy X in country Y?
    and so on.
    This will work much better if:
    1. You have presented and practised some of the hedging strategies covered above.
    2. You insist on the use of at least two of them in every response.
    3. You forbid all comments beginning with perhaps or maybe.  You can ban the words altogether, of course.

academic

Academic English

If your learners are studying English for Academic Purposes, they will need to work hard on getting the right tone in what they write.  There is a convention, for example, that we rarely write It is certainly obvious that ... preferring, in academic language, something like It seems strongly arguable that ... .  Stating that something is true simply challenges the reader to disagree or think of a counter example.
This is not the place for more detail but the same strategies that have been outlined here for spoken language will apply equally to formal, written prose.
This is especially true for the use of modal verbs, modal nouns, adjectives and adverbs and the use of appropriately modest copular verbs, replacing the certain be with less assertive verbs such as seem.


There is a separate language analysis guide on this site to epistemic modality which considers the area of expressions of likelihood.


There a short test on some of this if you want to do it.