1. What is this?
A bird
2. What are these sports?
billiards

chess

3. What can you see in this picture?
Blue sky
4. What are they?
One pillar pagoda
A tree
A bird
billiards

chess

blue sky
One pillar pagoda
A tree
possibility
It would rain this afternoon.
could
might
may

It should rain this afternoon.
The grass is wet. It must have rained.
Although “would, could, might, may” are used in conditionals, they can also be used to mean possibility. In this case, “would, could, might, may” mean the same. The speaker is not sure of the statement made when using these modals
It would rain this afternoon
could
might
may


It will possibly rain this afternoon
Maybe it will rain this afternoon
Maybe = perhaps
“Should” is used to indicate:
A recommendation, advice or obligation.
eg: Mary should study tonight.
You look tired. You should see the doctor.
Expectation; used to indicate something that the speaker expect to happen.
eg: It should rain this afternoon.
I expect it to rain this afternoon.
Must: logical conclusion; “must” is used to indicate that the speaker assumes something to be true from the facts that are available but is not absolutely certain of the truth.
The grass is wet. It must be raining.
We assume that it have rained because the grass is wet.
Diagram of degree of certainty:

Lower degree
would
could
might
may

Medium degree

should

Higher degree

must

Astronauts have to work in the sky lab for months
They might miss their families a lot
low
Read the following sentences and decide the degree of certainty:
Nam skips the class. He is playing computer games.
He might fail in his examination.
low
People must wear a helmet when traveling by motorbikes.
High
He’s got headache.
He should see the doctor.
Medium
Task A: Situation responses:
Work in pairs, use the given words to talk about possibility as in the example:
Dennis Tito, a Japanese, went into space. He has a lot of money.

He must be very rich.
rich
He wants to travel into space once in his life. He needs lots of money.
Save money

He must save money.
She got high scores on her final exam. She had spent much time on her study.

She must work hard at home.
work hard at home
Where are you going for your vacation?

I might go to Nha Trang.
Go to Nha Trang
The child is crying.
He might be hungry.
hungry
What’s wrong with Jim? He looks pale.

He must be very tired.
Tired
Task B: Talking about plans
Work in groups, ask and answer questions about your plans next summer vacation; use must, could, might, may.
I might go to Nha Trang to visit Vinpearl Land. I have ever gone there.
What are you going to do next summer vacation?
I would go to visit my grandparents. I haven’t seen them for a long time.
I would stay at home because I have to prepare for my entrance exam.
Read and complete the following sentences with words expressing degree of certainty such as: must, should, would
1. Mary is gaining weight. She ………….. go on a diet.
2. John’s lights are out. He …………… be asleep.
3. People ………….exercise twice a day to have a good health.
4. I …………… do that again if I had a chance.
should
should
must
would


Continue doing exercise.
Write a short paragraph about
your summer vacation.
THANK YOU FOR
your ATTENtion