Do you know how to use modal verbs to express certainty or possibility? Enhance your knowledge with a lesson given below and the grammar explanation to guide you better.

Check out these examples to see how must, might, may, could, and can't are used:

• That must be the new restaurant. There’s a crowd waiting outside.

• I’ve misplaced my wallet. It might be in my jacket, or it could be on the kitchen counter.

• You can’t be tired yet! We’ve only just started the hike.

Grammar explanation - Modals: deductions about the present

We use modal verbs for deduction, which means making a guess about whether something is true based on the information we have. The modal verb we choose shows how certain we are about the possibility. This explanation focuses on making deductions about the present or future.

1. Must

We use must when we are certain that something is true or it's the only logical possibility.

• That must be her office. I see her name on the door.

• He must work nearby; he’s always here at lunchtime.

• You must be exhausted after such a long journey.

2. might, may, could

We use might, may, or could when we think something is possible but we're not sure.

• She’s not answering her phone. She might be in a meeting.

• He’s not home yet. He could be running errands.

• We may experience some delays due to the storm.

These verbs all have the same meaning but may is more formal than might or could.

3. can't

We use can't when we are certain that something is not possible.

• It can't be much further. The map says we’re almost there.

• He can't have forgotten the appointment. I reminded him twice!

• She can't be happy with the decision. She argued against it.

As with all modal verbs, these are followed by an infinitive without to.

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