Modals - 50 items

Modal Verbs
Auxiliary verbs that express ability, possibility, permission, obligation, or certainty.

Auxiliary Verbs
Helping verbs that add meaning to the main verb.

Main Verb
The verb that shows the main action in a sentence.

Base Verb Rule
Modals are always followed by the base form of a verb.

No Tense Inflection
Modals do not change form (e.g., can stays can).

No Infinitive Form
Modals cannot be used with “to” (e.g., to can).

No “Do” Support
Modals form questions without do (e.g., Can you go?).

Direct Negatives
Add not to form negatives (e.g., cannot, should not).

Question Inversion
Modal verbs come before the subject in questions.

Single Modal Rule
Only one modal verb can be used per clause.

Ability Modals
Used to express skill or capability.

Can (Ability)
Used for present ability.

Could (Past Ability)
Used for general ability in the past.

General Past Ability
Describes abilities over a period of time (could).

Specific Past Ability
Describes a successful action (was/were able to).

Modals of Possibility
Express how likely something is.

May
Shows moderate possibility or permission.

Might
Shows lower possibility.

Could (Possibility)
Shows possible outcomes.

Must (Certainty)
Expresses strong logical conclusion.

Can’t (Impossibility)
Expresses something is not possible.

Degrees of Probability
Levels of certainty expressed by different modals.

Modals of Permission
Used to allow or ask for permission.

Can (Permission)
Informal permission.

May (Permission)
Formal permission.

Could (Permission)
Polite permission.

Modals of Request
Used to ask for help or action.

Politeness Scale
Can < Could < Would in level of politeness.

Modals of Obligation
Express duty or necessity.

Must (Obligation)
Strong, internal obligation.

Have To
External obligation or rule.

Internal Obligation
Comes from the speaker.

External Obligation
Comes from rules or outside forces.

Must Not
Indicates prohibition.

Don’t Have To
Indicates no necessity.

Modals of Advice
Used to recommend actions.

Should
Common modal for advice.

Ought To
More formal advice.

Should Have
Expresses regret or criticism.

Modals of Suggestion
Used to suggest ideas (shall, could).

Perfect Modals
Modal + have + past participle.

Must Have
Strong certainty about the past.

Might Have / May Have
Past possibility.

Could Have
Missed opportunity.

Should Have
Regret or criticism.

Can’t Have
Past impossibility.

Semi-Modals
Verbs like have to, need to, used to.

Pragmatic Function
How modals affect tone, politeness, and meaning.

Formal vs Informal Modals
May (formal) vs can (informal).

Common Errors with Modals
Include double modals, wrong verb form, and incorrect tense usage.