Modal Verbs

Expresses present ability or informal permission.

"She can speak three languages fluently."

Past ability, or a polite/tentative possibility.

"When I was young, I could run for miles."

Formal permission, or a real present/future possibility.

"You may leave once the exam is over."

A weaker, less certain possibility than 'may'.

"It might rain later, so take an umbrella."

A substitute for 'can' in tenses where 'can' cannot be used.

"I will be able to help you tomorrow."

Expresses permission (a neutral alternative to may/can).

"Visitors are allowed to park in the north lot."

Describes a past habit or state that is no longer true.

"I used to walk to school every day."

Indicates something is quite likely.

"It may well rain before the match ends."

A tentative way of raising a possibility.

"The delay could possibly push the launch to Friday."

A confident logical deduction (near certainty).

"The lights are off; they must be asleep."

A confident negative deduction (near impossibility).

"She can't be at home - her car is gone."

Uncertain deduction about a present situation.

"He's late; he might be stuck in traffic."

A confident guess about the past.

"The ground is wet — it must have rained."

Rejects a past possibility with confidence.

"She can’t have left already; her coat is here."

A tentative guess about the past.

"He might have missed the train."

Expresses an expectation or mild regret about the past.

"They should have arrived by now."

Predicts a completed action by a future point.

"By June we will have finished the project."

Describes an unreal or imagined past result.

"I would have called, but my phone died."

Strong obligation or necessity, often from the speaker.

"You must wear a seatbelt in the car."

External obligation imposed by rules or circumstances.

"I have to submit the report by Friday."

Advice or a mild recommendation.

"You should see a doctor about that cough."

Advice or duty, slightly more formal than 'should'.

"We ought to thank them for their help."

Necessity; 'needn't' expresses a lack of necessity.

"You needn't worry about the bill."

Strong advice with a hint of warning.

"You had better leave now or you'll miss the train."

States an expectation, rule or arrangement.

"You are supposed to sign in at reception."

Expresses a formal instruction or scheduled plan.

"All staff are to report by nine o’clock."

An informal, emphatic form of have to.

"I have got to finish this report tonight."

Used as a bare modal, mainly in questions and negatives.

"Need I remind you of the deadline?"

Prohibition - something is not allowed.

"Passengers must not lean out of the window."

Impossibility or something that is forbidden.

"You cannot park here during rush hour."

No obligation - it is optional.

"You don't have to come if you're tired."

Formally withholds permission.

"Candidates may not use calculators in this exam."

A formal or legal prohibition.

"Members shall not share their passes."

Says that something is not necessary.

"You needn’t wait for me — start without me."

A plain way of saying something is unnecessary.

"You don’t need to bring anything."

Polite requests, offers, and hypothetical situations.

"Would you pass me the salt, please?"

Willingness, promises, and future intentions.

"I will call you as soon as I arrive."

Offers and suggestions, chiefly with 'I' and 'we'.

"Shall we begin the meeting?"

A polite way to make a request or suggestion.

"Could you help me carry these boxes?"

A very polite way to make a request.

"Would you mind closing the window?"

Offers or suggests a shared action.

"Shall we begin?"

A friendly way to suggest an idea.

"Why don’t we meet at noon?"

Proposes doing something together.

"Let’s take a short break."

A polite request form.

"Could you pass the salt, please?"