Unit 6.2

Modals of Probability

Introduction

Modals of deduction and speculation are also called modals of probability. We find them when we want to make a guess about something.

Different modals can be used depending on how sure we are about a situation.

Form

The most commonly used modals of probability are can, could, may and must.

They have different structures.

Can/Can’t

The affirmative form is:
Can + bare infinitive.

The negative form is:
Can’t + bare infinitive.

Could/couldn’t

The affirmative form is:
Could + bare infinitive.

The negative form is:
Could not + bare infinitive.

May/may not

The affirmative form is:
May + bare infinitive.

The negative form is:
May not + bare infinitive.

Might/might not

The affirmative form is:
Might + bare infinitive.

The negative form is:
Might not + bare infinitive.

Must

The affirmative form is:
Must + bare infinitive.

The negative form is:
Must + not + bare infinitive.

Should/should not

The affirmative form is:
Should + bare infinitive.

The negative form is:
Should + not + bare infinitive.

Example

  • He can’t go to school because there is a heavy snowfall outside.
  • She couldn’t paint this wall with watercolours.
  • Environmental problems and natural disasters may create problems for people.
  • There might be traffic on the main road because of the festival.
  • Nuclear energy must be harmful for the environment.
  • Thunders and lightnings should make noise.

Use

We use modals of probability when we talk about a present situation.

We use:

  • can: to talk about something that happens sometimes, something possible;
  • could, may/might: for probabilities and predictions;
  • must: when we are sure about something;
  • should: to make a guess about something that is likely to happen.

Summary

Modals of probability, also called modals of deduction and speculation, are used when we want to make a guess about something. Different modals of probability can be used depending on how sure we are about a present situation.

The most commonly used modals of probability are can, could, may and must.

We use:

  • can/ can’t followed by a verb in the bare infinitive form, to talk about something that happens sometimes, something possible;
  • could/couldn’t, may/may not/might/might not followed by a verb in the bare infinitive form, to talk about probabilities and predictions;
  • must is followed by a verb in the bare infinitive form, when we are sure about something;
  • should/should not followed by a verb in the bare infinitive form, to make a guess about something that is likely to happen.

For example:
— “I may not be on time tomorrow for dinner, because we will have a meeting at work.” = I am predicting that I will be late for dinner tomorrow.
— “He must be at work now.” = I am sure that he is at work now.

Let’s revise this content within the {Form} section. Take a look at the {Example} section that shows its use within a context.

Exercises


Translations

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