1. Modality may be divided into 2
types

2. • INTRINSIC: those such as
permission, obligation and volition which
involve some kind of intrinsic human control
over events .

3. • EXTRINSIC: those such as possibility, necessity
and prediction, which do not primarily involve
human control of events, but do typically
involve human judgement of what is or what
is not likely to happen.

4. Central Modals:
• These are nine central modal verbs:
CAN, COULD, MAY, MIGHT, SHOULD, WILL, W
OULD, SHALL.

5. • Semi-Modals: (also called periphrastic modals or
quasi-modals) are multi-word constructions that
function like modal verbs.
• Quirk uses the expression “marginal auxiliaries”
to apply to 4 categories: marginal modals, modal
idioms, semi-auxiliaries and catenative verbs.
•

6. • Marginal Modals:
DARE, NEED, OUGHT TO, USED TO.

7. • Modal Idioms:
HAD BETTER, WOULD RATHER/SOONER,
HAVE GOT TO, BE TO.

8. • Semi-Auxiliaries: HAVE TO, BE ABOUT TO, BE
ABLE TO, BE BOUND TO, BE GOING TO, BE
OBLIGED TO, BE SUPPOSED TO, BE DUE TO.
•

9. • Semi-Auxiliaries:
HAVE TO, BE ABOUT TO, BE ABLE TO, BE
BOUND TO, BE GOING TO, BE OBLIGED TO,
BE SUPPOSED TO, BE DUE TO.

10. • Catenatives: APPEAR TO, HAPPEN TO, SEEM
TO, GET +-ed participle, KEEP (ON) + -ing
participles.