Modal Auxiliaries

​Modals

By Marcela Natiola

Multiple Choice

I’m not sure, but he ___ be in the library right now.

• might

• would

• will

• must

Multiple Choice

That story is impossible! It ___ be true.

• can

• could

• can't

• couldn't

Multiple Choice

Don’t worry, your package ___ arrive tomorrow—it’s already shipped.

• should

• might

• can

• could

Multiple Choice

Look at those dark clouds. It ___ rain soon.

• will

• shall

• might

• must

Multiple Choice

She won first place in the competition. She ___ be very happy.

• can

• must

• will

• can't

Modal Auxiliaries of Certainties

1. I can identify modal auxiliaries that express degrees of certainty (low, moderate, and strong).

2. I can distinguish between sentences that show certainty, possibility, and impossibility.

3. I can construct original sentences using appropriate modals depending on certainty.

Learning Targets

Modal verbs of certainty are special helping verbs we use to show how sure or unsure we are about something.

Low Certainty

It's POSSIBLE but NOT CERTAIN

It might rain later.

It's possible, but not certain. Clouds don’t always bring rain, so we are not sure.

Moderate Certainty

The speaker is fairly sure; the event is expected or likely to happen.

It should rain this afternoon.

Based on the sky, it’s very likely to happen.

Strong Certainty

The speaker is completely sure; the event is true or impossible.

It must be about to rain because the clouds are very dark.

The evidence (black clouds) makes it very certain.

Low Certainty

It's POSSIBLE but NOT CERTAIN

She could be late for class.

You are guessing the reason. There are other possibilities, like she could be excited to meet someone or just exercising.

Situation: You see your friend running towards the school gate.

Moderate Certainty

The speaker is fairly sure; the event is expected or likely to happen.

She usually hurries when she’s late.

Based on past behavior, this is likely. It’s not 100% certain, but experience suggests it’s probable.

​Situation: You see your friend running towards the school gate.

Strong Certainty

The speaker is completely sure; the event is true or impossible.

She is clearly running for an important reason.

Seeing her run quickly makes you almost sure that there is an important reason behind it.

​Situation: You see your friend running towards the school gate.

Situation: You see someone carrying an umbrella inside the classroom.

• Low certainty: He could be using it as a prop.

• Moderate certainty: He probably forgot to leave it outside.

• Strong certainty: He's obviously concerned about getting wet.

Situation: Your friends look sad while checking their phone..

• Low certainty: They may have gotten bad news because they are frowning.

• Moderate certainty: They generally look upset when reading messages like that because the messages are usually disappointing.

• Strong certainty: They are undoubtedly upset about something important because they started crying.

• perhaps, maybe, may, might, could, sometimes, occasionally, seldom, possibly, conceivably

Low Certainty

Modal Verbs of Certainty

Moderate Certainty

• likely, probably, can, ought to, should, would, usually, frequently, often, regularly, majority, generally, tends to, rarely

Strong Certainty

• is, will, can, not, must, undoubtedly, definitely, clearly, always, never, undeniably