skip navigation

Will / Might

Degrees of certainty

Polar Bears straned on an iceflow
 

 

Degrees of Certainty – Present and Future
CERTAIN ALMOST CERTAIN UNCERTAIN

certainThe modal will expresses a person's attitude toward the factuality of a situation, the likelihood that a situation is true or false. The person infers this from known details. Will expresses that the speaker is certain.

probable Must expresses that the speaker is near certain. Cannot and could not  (neg. ) also express near certainty.

possibleMay, might, and could express uncertain opinion, a guess based on very little information. Might is considered slightly less certain than may by some speakers.

MODAL    

Polar bears are starving.  (dying of hunger)

Polar bears will starve.
Polar bears are going to starve.
 

Polar bears must be starving.

Polar bears may be starving.
Polar bears might be starving.
Polar bears could be starving.
NEGATIVE MODAL   DOUBT

Polar bears won't starve.

Polar bears must not be starving.
Polar bears can't / couldn't be starving.
 

Polar bears may/ might not be starving.
CLAUSE    

I am sure that polar bears are starving.
I am certain that polar bears are starving.

It is likely that polar bears are starving.
It is probable that polar bears are starving.
It is doubtful that polar bears are starving. 
 

It is possible that polar bears are starving.
Polar bears will possibly starve.

clue (n.) – information that helps you understand the reasons why something happens
factual (adj.) – something based on fact, something known to be true
factuality (n.) – the degree to which one can accept something as fact, true; based on facts; also called epistemic (CaGEL 178)
infer (v.) – to form an opinion that something is probably true because of information that you have
inference (n.) – an opinion that is formed on details or knowledge that you have
likelihood (n.) – possibility, probability; whether something true or false
speculation (n.) – a guess about the possible causes or effects of something, without knowing all the facts or details
starve (v.) to die of hunger;  starving (adj.) or (participle); starvation (n.) – suffering or death caused by not enough food.

You may be right. (low certainty) / You might be right  (lower certainty) The past modal form expresses "remoteness". (CaGEL3 §9.8.3.b) Grammar Notes

See Modal Review – Possibility – weak to strong (epistemic modal use)

 

 

 

 

Was, Must have, Might have

Degrees of Certainty – Past

 

 

 

Degrees of Certainty – Past
VERY CERTAIN –  REFLECTION ALMOST CERTAIN  – INFERENCE UNCERTAIN – SPECULATION

certainThe past tense or past perfect express fact based on known information or details.

probablePast modals must have and could not have express opinion based on inference, putting together known details and coming to a conclusion.

possiblePast modals might have and could have express opinion based on very little information, a guess (with perhaps other interpretations.)
MODAL    

Polar ice melted.
Polar bears lost their icy habitat.

Polar bears must have lost their food supply  (Clues: there is no ice, so there are no seals. Polar bears have no platforms from which they can hunt seals.)

Polar bears may/ might/ could have left their cubs.

NEGATIVE MODAL   DOUBT

Polar bear cubs didn't die from the cold.

Polar bears could not have fed their cubs.

Polar bears may/ might not have found food for their cubs.
 

CLAUSE    

I am/was sure that polar bear cubs died from starvation

It is/was likely that polar bears found no seals to feed their cubs.

It is/was doubtful that the polar bears found any ice from which to hunt seals.
 

reflection (n.) – remembering the past 
inference (n.) –   something that you think is true, based on information that you have
speculation (n.) –  a good guess; likely

Also see Might / Must have – past guesses and inferences.

 

 

 

 

Must

Two Meanings – Inference / Necessity

 

 

 

Must (inference) vs. Must (necessity)
#1 MUST

probableA speaker uses must to express a logical conclusion, an inference based on clues or information that one knows.  The speaker's certainty is "strong".
AN INFERENCE / A CONCLUSION

Polar bears go into seaside towns looking for garbage.
Polar bears must be hungry.  (near certain)

Ice no longer covers the polar regions all year.
Polar bears must be suffering with this change. (near certain)

A normally peaceful bear attacked and killed some arctic campers. The bear must have been looking for food.   (near certain)
#2 MUST

obligation (strong)A speaker also uses must to express obligation, duty, or necessity, something that someone "has to do". The speaker's opinion is "strong".
NECESSITY / OBLIGATION

Polar bears must be fed or relocated. (strong – necessity)

Polar bears must swim long distances to find ice and seals to eat.  (strong – necessity)

The campers had to shoot the bear.
(Necessity in the past tense is expressed with "had to" not "must have".)
 

inference (n.) –   something that you think is true, based on information that you have
See Should /Must and Must / Must have.
Also see Modal Review – Obligation.

 

 

 

 

Modals

Word Order

 

 

 

AUX VERB SUBJECT MODAL VERB BASE COMPLEMENT TAG CLAUSE
STATEMENT          
 

Polar bears

could

die 

of starvation.

 

 

 

may / might

 

 

 

 

 

must

be 

hungry. 

 
QUESTION          

Could

polar bears

 

die 

of starvation?

 

*May/ Might

 

 

 

 

 

Is it possible that     

polar bears

will

die 

of starvation?

 
TAG QUESTION          

 

Polar bears

could

die

of starvation,

could n't they? 

 

 

may/ might

 

 

*may/ might they not?

 

 

must

be 

hungry. 

must n't they? 

It is possible that

polar bears

will

die

of starvation.

isn't it? 
 

NEGATIVE          
 

Polar bears

may / might not

die 

of starvation.

  

 

Polar bears

may not

die 

of starvation.

 

 

Polar bears

could not

die 

of starvation.

 

It is doubtful that
It is unlikely that
 

polar bears

will

die 

of starvation.

 
PAST          
 

Scientists

might have

predicted

this.

  

 

Scientists

may have 

predicted

this.

 

 

Scientists

could have 

predicted

this.

 
NEG. PAST          

 

Scientists

might not have

predicted

this.

 

 

 

Scientists

may not have

predicted

this.

 

 

Scientists

could not have

predicted

this.

 
W / ADVERB          

 

We

might suddenly

lose

this species.

 

 

 

We

may eventually

lose

this species.

 

 

We

could also

lose

this species.

 

It is possible that
Possibly,
 

we

will soon

lose

this species.


 

 

 

 

 

 

Grammar Notes

Grammar Descriptions

Advanced

 

 

AZAR / BIBER HUDDLESTON / SWAN
AZAR HUDDLESTON (CaGEL)

Will expresses a high degree of certainty. (UUEG 10-1-2)

  • 100% degree of certainty → He is sick / He will be sick. (future) → Speaker feels sure.

Must — expresses a strong degree of certainty about a present situation, but the degree of certainty is still less than 100%.  (10-1)

  • 95% degree of certainty → He must be sick.

Might — may, might, could express a weak degree of certainty. (10-1)

  • 50% degree of certainty → He might be sick. → perhaps, maybe "I am making a guess." "There are other possibilities."

     

Modality (3 §9.2.2)  See Modality for epistemic, deontic, and dynamic examples.

epistemic modals "knowledge" – what the speaker believes is probable; likelihood based on inference (factuality)  He must / may / might be here.

Will conveys a lower degree of modal meaning…  (Is it opinion or prediction?) (CaGEL 3 §9.5)  Will expresses futurity (epistemic) → He will be two years-old tomorrow.

Must  has the same epistemic strength as will, and must in its central-epistemic use can generally replace will with relatively little change of meaning.

May expresses possibility (epistemic) and is often used subjectively: I don't know that the proposition is false and put it forward as a possibility.  → He may stay here. (possibly)

Might  (3 §9.8) tentative (epistemic) → You may be right. (low % of possibility)  / You might be right. (lower % of possibility than may  (3 §9.8.3.b)
 

BIBER (LGSWE) SWAN (PEU)

Will / Might    There is no formal future tense in English. (6.2.1.3) 
Modals and semi-modals can be grouped into three categories: (485)

  • permission/ possibility / ability: can, could, may, might
  • obligation / necessity: must, should, had better, have (got) to, need to ought to, be supposed to
  • volition / prediction: will, would, shall, be going to

 Semi-modals → be going (to), ought (to), have (to), need (to), had better, have got (to), be supposed (to)
 

Will can express certainty or confidence about present or future situations. (629.3)

  • certainty → As I'm sure you will understand, we cannot wait any longer.

May / Might expresses the chance (possibility) that something will happen, or is happening. (Might is more doubtful than may.) (339)

  • unlikely → Peter might phone.  (possible, but not very likely, more hesitant than may)  I may go. (50% chance)  I might go. (30% chance) (339.2)

 

 

Resources

 

 

 

 

Practice 1

Scientists' Findings

Polar Bear

 

 

 

What can we do to help polar bears?

In May 2008, the U.S. and several countries listed the polar bear as a threatened species.  In a short time, a large amount of polar ice has melted.

Soon, a large number of polar bears will lose their habitat. Biologists might be able to do some temporary things, such as building ice platforms for polar bears to rest upon. However, most scientists agree that this will not help polar bears hunt for food or build their dens.

The only way to help polar bears will be to slow down global warming. That might be possible if we can lower green house gas emissions. Human activities will need to change. 

Natural fluctuations in the climate system will continue with global warming. As a result, scientists can't predict when all the ice will melt; it may be sooner than later than.  But it is going to happen. It is doubtful whether we can reverse the melting of polar ice, but we can slow it down.

biologist (n.)  – a scientist who studies life forms, living things (biology)

den (n.) – an animal home in the ice or snow; an ice cave

floating (adj.) – rests on top, on the surface, of water

fluctuation (n.) – continual change, from one point to another: hot and cold, rain and drought.

global warming (n.) – rising temperatures on earth

green house gas emissions (n.) – toxic gases from cars, factories, and other human activities  (GHG)

melt (v.) – when ice changes to water; solid becomes liquid

platform (n.) – a surface raised above the level of the surrounding area; an artificial ice island

reverse (v.) – stop, or turn it around

threatened (adj.) – in danger of extinction (no more of its type existing)

 

"Global Warming." Polar Bears International, 2013. polarbearsinternational.org

 

 

 

How certain is the writer?
  1. Select the response that best completes the sentence. 
  2. Click the check 1-10 button at the bottom of the practice to reveal the answers after you finish, or
    click the individual "check" buttons #1-10 to compare responses as you go.

 

1.
Soon, a large number of polar bears will lose their habitat. 

     

2.
Biologists might be able to do some temporary things, such as building ice platforms for polar bears to rest upon.

   

3.
However, most scientists agree that this will not help polar bears hunt for food or build their dens.

   

4.
The only way to help polar bears will be to slow down global warming.

   

5.
That might be possible if we can lower green house gas emissions.

   

6.
Human activities will need to change. 

   

7.
Natural fluctuations in the climate system will continue with global warming.

   

8.
As a result, scientists can't predict when all the ice will melt; it may be sooner than later than.

   

9.
But it is going to happen.

   

10.
It is doubtful whether we can reverse the melting of polar ice, but we can slow it down.

   

 

 

 

 

 

 

Practice 2

Polar Bear Diet

a ringed seal in an ice hole

 

 

A Polar Bear's Diet

The main diet of the polar bear is the Ringed Seal. 

A seal cuts several breathing holes in the ice because it has to surface for air every five to fifteen minutes.

A polar bear looks for a breathing hole so that it can prey on a seal.  It waits several hours or days for a seal to come up through its breathing hole.  Polar bears are very smart and patient to catch a seal. 

 

A polar bear sometimes stalks a ringed seal that is sunbathing on the ice.  The bear crawls forward very slowly and freeze in place when the seal lifts its head.  At about 20 feet, the bear runs and kills the seal before it can escape back into the sea.

Another source of food is the Beluga whale. A whale sometimes gets trapped in the ice. If so, it becomes easy prey for polar bears. In such an event, one sometimes sees twenty or more polar bears surrounding and eating one whale carcass.

breathing hole (n.) an air hole in the ice for mammals

prey (v.) – hunt and eat  prey (n.) – the animals that are hunted and eaten by other animals

stalk (v.) – to follow or get closer to an animal slowly and quietly in order to catch and kill it

surface (v.) – swim to the top of the water (the air above)

surround (v.) – go on all sides of something; encircle

trapped (adj.) – caught, stuck, unable to move, not free

 

"Hunting and Eating." Polar Bears International. 2013 polarbearsinternational.org

 

 

 

Is the activity likely or unlikely to happen?
  1. Select the word from the list that best expresses the degree of certainty. 
  2. Click the check 11-20 button at the bottom of the practice to reveal the answers after you finish, or
    click the individual "check" buttons #11-20 to compare responses as you go.

 

11.

12.

13.

14.

15.

16.

17.

18.

19.

20.

 

 

 

 

 

 

Practice 3

Will Polar Bears Survive?

Grizzly and polar bear fighting

 

 

 

Read and Rewrite

New research shows that polar bears (survive) in the past through warm periods. And a few scientists say they (do) so again in the future.

A study of polar bears and brown bears indicates that the two (split) around five million years ago. There (be) interbreeding between the two throughout their evolutionary history.

Polar bears (be) now very different from the grizzly bears. Polar bears are very specialized to a sea ice environment. Grizzly bears are very well-adapted to a land environment. A few scientist believe they (interbreed and survive).

Other scientists believe that if they do interbreed, the new creature would no longer resemble a polar bear.  The genes would be passed on, but the bear (be) something very different.

The fact that they have survived in the past does not mean they (survive) through this next global warming, at least not as large, white, sea-hunting bears.

Unless we take action to decrease greenhouse gas emissions, polar bears (face) an uncertain future in which the climate continues to warm. If temperatures rise higher than ever before, polar bears (not survive).

environment (n.) – the area around

gene (n.) – the DNA; a part of a cell in a living thing that controls what it looks like, how it grows, and how it develops

interbreed (v.) – breed or mate with a closely related individual, as in a small, closed population.

species (n.) – related individuals that resemble one another, are able to breed among themselves, but are not able to breed with members of another species.

split (v.) – broke apart; became different

survive (v.) – to continue to live after an accident, war, illness, or natural disaster

 

 

 

 

Rewrite the paragraph to include expressions of doubt and certainty.  (See present and past examples above.)
  1. Edit the sentence(s) in the text box.   Answers may vary.
  2. Click the check 21-30 button at the bottom of the practice to reveal the answers after you finish, or
    click the individual "check" buttons #21-30 to compare responses as you go.
21.
New research shows that polar bears (survive) in the past through warm periods.  (reflection on a fact)


22.
And a few scientists say they (do) so again in the future.  (certain)


23.
A study of polar bears and brown bears indicates that the two (split) around five million years ago. (conclusion)


24.
There (be) interbreeding between the two throughout their evolutionary history. (speculation)


25.
Polar bears (be) now very different from the grizzly bears. (certain)


26.
A few scientists believe they (interbreed and survive). (speculation)


27.
The genes would be passed on, but the bear (be) something very different. (speculation)


28.
The fact that they have survived in the past does not mean they (survive) through this next global warming, at least not as large, white, sea-hunting bears. (certain)


29.
Unless we take action to decrease greenhouse gas emissions, polar bears (face) an uncertain future in which the climate continues to warm. (certain)


30.
If temperatures rise higher than ever before, polar bears (not survive). (doubt)