C2 Grammar WPWord Play
Home›C2›Grammar›Advanced Modality
Ch 3

Advanced Modality

Epistemic vs deontic · modal adverbs · past modals

Two systems of modality

Modality expresses speaker stance — judgment of likelihood or social positioning. At C2 you distinguish two systems precisely.

Epistemic (probability)
judgment of likelihood: It must be raining (I'm sure)
Deontic (obligation)
social/moral force: You must apologise (you are obliged to)
Dynamic (ability/willingness)
internal capacity: She can swim

Same form, different meaning

Epistemic (likelihood)
She must be tired. (I deduce)
He can't be home — his car's gone.
It might rain. (probability)
Deontic (obligation)
You must apologise. (I require)
You can't park here. (it's forbidden)
You might consider it. (suggestion)

Modal adverbs — adverbial modality

High certainty
certainly · undoubtedly · clearly · obviously · evidently · plainly
Medium certainty
presumably · apparently · seemingly · ostensibly · in all likelihood
Low certainty
perhaps · possibly · conceivably · arguably · debatably
Reported (hearsay)
allegedly · reportedly · supposedly · purportedly
The minister allegedly accepted bribes.
The plan is arguably the best option.

Modality in formal writing

Tentative claim
It may be argued that... / There appears to be a correlation.
Concession
It could be argued otherwise, but...
Recommendation
It would be advisable to... / We would recommend that...
Speculation
One might suppose that... / It is conceivable that...
Inference
This would suggest... / The results imply...

Past modality — the full range

must have + PP (certain deduction)
She must have left already.
can't have + PP (impossible deduction)
He can't have done it.
should have + PP (regret/criticism)
You should have told me.
would have + PP (hypothetical)
I would have helped, but I didn't know.
could have + PP (possibility / criticism)
She could have been a doctor. / You could have asked.
may/might have + PP (uncertain past)
They may have missed the train.

Common mistakes

She must to apologise.
→
She must apologise.
modals never take "to"
He could of helped us.
→
He could have helped us.
"of" never replaces "have" after modal
It allegedly that he stole the money.
→
He allegedly stole the money. / It is alleged that he stole...
modal adverb position: before main verb

Recap

Three systems
epistemic (likely) · deontic (obliged) · dynamic (able)
must, can — context disambiguates
Modal adverbs
certainty scale: certainly → presumably → arguably
allegedly, presumably
Formal patterns
it may be argued / it would be advisable / one might suppose
academic hedging
Past modals
must/can't/should/would/could/might have + PP
should have called
Practice now →