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Polar Bears straned on an iceflowWill / Might

Expressing degrees of certainty

 

 

 

 

 

 

Present & Future Uncertainty
VERY CERTAIN UNCERTAIN UNCERTAIN NEGATIVE

Use will or (be) going + verb to express certainty about a future activity, event.

Use may, might, could to express uncertainty, a guess, about a future activity, event.

Use may, might or an expression of doubt to indicate uncertainty about or likelihood of a future activity or event.


Polar bears will disappear. certainly


Polar bears may disappear. possibly


Polar bears may / might not disappear. possibly not

Polar bears are going to disappear. certainly

Polar bears might disappear. possibly

It is doubtful that polar bears will disappear. possibly not

 

Polar bears can / could disappear. potentially

It is unlikely that polar bears will disappear. possibly not

100% certain
The speaker is 100 % certain that they will disappear.
 
60% certain
The speaker is uncertain they will disappear.
60% certain
The speaker is uncertain they will not disappear.
 

guess (n.) – an attempt to answer a question or make a judgement when not sure whether it is correct
potentially (adv) – something that may become true in the future under the right (or wrong) conditions

 

 

 

Past Uncertainty 
VERY CERTAIN  -  Reflection UNCERTAIN  -  Speculation UNCERTAIN NEGATIVE - Speculation

Use past tense to comment with certainty on a past activity or event.

Use may, might, could to express uncertainty, a guess, about the occurence of a past activity or event.

Use may have, might have or an expression of doubt to indicate uncertainty about the occurence of a past activity or event.

Dinosaurs disappeared due to a meteor strike.

Dinosaurs may have died from disease

They may not have had resistance to disease.

Dinosaurs died due to a global weather changes.

Dinosaurs might have died from starvation.

They might not have had enough to eat.

 

Dinosaurs could have died from cosmic radiation.
 

They might not have had shelter from radiation.

reflection (n.) – remembering the past 
speculation (n.) –  an educated guess
resistence
(n.) –  ability to fight off

 

 

 

 

Sentence Types

Word Order

 

SENT TYPE AUX VERB SUBJECT MODAL VERB BASE TAG CLAUSE

STATEMENT

possibly

 

 

Polar bears

 

might

 

disappear. 

 

 

possibly

 

Polar bears

may

disappear. 

 

possibly

 

Polar bears

could

disappear. 

 

QUESTION

potentially

 

Could

 

Polar bears

 

 

 

disappear? 

 

 

*Might

Polar bears

 

disappear? 

 

*May

Polar bears

 

disappear? 

 

possibly

Is it possible that   

Polar bears

will

disappear? 

 

TAG QUESTION

 —

 

 

 

Polar bears

 

might

 

disappear,

 

might they not?

 

Polar bears

may

disappear,

*may they not?

potentially

 

Polar bears

could

disappear,

could n't they? 

possibly

It possible that

Polar bears

will

disappear,

isn't it? 

NEGATIVE

possibly not

 

 

Polar bears

 

might not

 

disappear. 

 

possibly not

 

Polar bears

may not

disappear.

 

potentially not

 

Polar bears

could not

disappear.

 

possibly not

It is doubtful that
It is unlikely that

Polar bears

will

disappear.

 

PAST

past possibility

 

 

Scientists

 

might have

 

predicted this.

 

past possibility

 

Scientists

may have 

predicted this. (but they didn't.)

 

lost opportunity

 

Scientists

could have 

predicted this.

 

NEG. PAST

past possibility

 

 

 

Scientists

 

might not have

 

predicted this.

 

 

past possibility

 

Scientists

may not have

predicted this.

 

an impossibility

 

Scientists

could not have

predicted this.

 

W / ADVERB

possibly

 

 

 

We

 

might suddenly

 

lose this species.

 

 

possibly

 

We

may eventually

lose this species.

 

possibly

 

We

could also

lose this species.

 

possibly

It is possible that
Possibly,

we

will soon

lose this species.


 

*awkward sounding
A tag question can also occur with a negative main sentence and a postive final question: Polar bears couldn't disappear, could they?   Related page: And so / too   

Related page: Modal Agreement 

 

 

 

 

AuthorPractice 1

How Certain is the Speaker?

 

 

 

Decide what the meaning of the verb in the sentence is.  
  1. Select your response.
  2.  * indicates an incorrect response.
  FEEDBACK YOUR RESPONSE


Stephen King's latest work could be a nightmare for book publishers.


 


2. He will publish his books on the Internet.


.
 
3. The first chapter will be free, then he might ask readers to pay $1 for the next chapter.

.

4. If enough readers pay $1, he will write the next chapter in the series.


5     In the past, King's dealings with publishers have been unsatisfactory. They might not have shared profits with him.




 
   

 

 

 

 

Practice 2

Expressing Doubt and Certainty

 

 

Decide which modal can complete the sentence.

Select your response. * indicates an incorrect response.

Read the hint box for additional information.

 

# FEEDBACK YOUR RESPONSE

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