Modals verbs

Modal Verbs Certainty

What are?

Structure

Use

Modal verbs certainty are deductions that by themselves cannot go alone, you need a subject+deduction+infinitive

The Modal verbs certainty are:

Can't it be almost always impossible for this prediction to be true

May/might/could be half as likely to be true

The Must, that is used when the prediction you know is true

When the deduction is about habitual and everyday situations or the main verb is a stative verb, the modal verb is followed by an infinitive.

The Modal verbs certainty are:

MUST>>>Subject + must + infinitive

May/might/could>>>Subject + may/might + not + infinitive

Must>>>Subject + can't + infinitive

However, we will use the modals with the verb to be followed by a gerund when it comes to deductions about temporal situations and actions that happen at the precise moment in which it is spoken.

MUST>>Subject + must + be + gerund

May/Might/Could>>Subject + may/might + not + gerund

Must>>Subject + can't + be + gerund

We use must when we have reason to be sure of something.

Example:

Where is your sister?

She must be lying on the sofa.

Might, may and could are used about situations in the present when the speaker is unsure of the deduction or assumption he or she is making because of lack of information or because it is not evident.

Example:

What language are they speaking?

I don't know. It might/may/could be Swedish.

Might, may and could are also used when the speaker is unsure of an assumption he is making about the future.

Example:

I may tell you the secret.

It might not be sunny tomorrow.