Modals - 20 items

Modal Verbs

Auxiliary verbs that express attitude, possibility, ability, obligation, or permission.

Auxiliary Verb

A helping verb that supports the main verb to add meaning (modals are a type of auxiliary).

Base Verb Rule

Modals are always followed by the base form of a verb (e.g., can run, not can runs).

No Tense Inflection

Modals do not change form regardless of subject or tense (e.g., he can, not he cans).

No Infinitive Form

Modals cannot be used with “to” (e.g., to can).

No “Do” Support

Modals form questions and negatives without using do (e.g., Can you go?).

Direct Negatives

Modals form negatives by adding not (e.g., cannot, should not).

Question Inversion

Modals come before the subject in questions (e.g., Can you swim?).

Modals of Ability

Express skill or capability (e.g., can, could).

Specific vs General Past Ability

Could = general past ability; was/were able to = specific successful action.

Modals of Possibility

Show likelihood (e.g., might, may, could).

Modals of Certainty

Express strong conclusions (e.g., must = very certain, can’t = impossible).

Modals of Permission

Used to ask or give permission (can informal, may formal, could polite).

Modals of Obligation

Express necessity or duty (must = strong/internal, have to = external).

Prohibition vs No Necessity

Must not = forbidden; don’t have to = optional.

Modals of Advice

Used to give recommendations (should, ought to).

Perfect Modals

Modal + have + past participle; used to talk about past (e.g., might have gone).

Missed Opportunity (Could Have)

Indicates something possible in the past that did not happen.

Double Modals Error

Using two modals together is incorrect (e.g., can must).

Pragmatic Function of Modals

Modals affect tone, politeness, certainty, and meaning in communication.