1. Conclusions: Must, Have (got) to, May, Might, Could, Can’t11
Conclusions: Must, Have (got) to, May, Might, Could, Can’t
A Visit to the Doctor
Focus on Grammar 3
Part VIII, Unit 37
By Ruth Luman, Gabriele Steiner, and BJ Wells
Copyright © Pearson Education, Inc. All rights reserved.

2. Am I OK? So, what seems to be the problem?
There are several possibilities.
Well, I have terrible pain in my stomach.
What could the problem be?
We’ll need to take some
X-rays and do some tests to find out.

3. Meaning
We often make guesses and draw conclusions about present situations using the information we have.
100% Certain
0% Certain
Positive
Negative
must
have (got) to
may
might, could
can’t, couldn’t
must not
may not
might not
We use modals to show how certain or uncertain we are about our conclusions.

4. Affirmative Conclusions
When we are almost 100% certain, we use must, have to, or have got to to state affirmative conclusions.
Mr. Jones must have an ulcer.
I looked at all the test results, and I talked to the patient. I believe that…
He has to be in pain.
He’s got to be very uncomfortable.

5. Possibilities I see something unusual. Mr. Jones could have an ulcer.
When we are less certain about our conclusion, we use may, might, or could to express that something is possible.
I see something unusual.
Mr. Jones could have an ulcer.
He may have an infection.
He might be very sick.

6. Practice 1 This might be … 100% Certain must have (got) to may
Look at each part of the photograph one at a time. Try to guess what it is. Increase the certainty of your guesses by using the appropriate modals.
Practice 1
100% Certain
This might be …
must
have (got) to
may
might, could
0% Certain
An X-ray of the heart
and lungs.

7. Negative Conclusions 1 It can’t be an infection. The X-rays look good.
Use can’t and couldn’t when you are almost 100% certain that something is impossible. Use must not when you are slightly less certain.
It can’t be an infection.
The X-rays look good.
The patient couldn’t have heartburn.
It must not be serious.

8. Negative Conclusions 2
Use may not and might not when you are even less certain.
Your illness might not be serious.
You may not need to stay in the hospital.

9. Questions Use can and could in questions. What can the problem be?
The test results are not clear.
Could the patient need surgery?

10. It must be cotton fibers.
Look at the objects under a microscope. Ask and answer questions about possibility. Use positive and negative modals.
Practice 2 1.
Example: 2.
It can’t be skin. 5.
It may be a feather.
What could it be?
It must be cotton fibers. 3. 4.
stomach of a spider eye of an insect a feather
cotton fibers tongue of a snail skin
(#5)
(#2)
(#3)
(Example)
(#4)
(#1)

11. Short Answers In short answers, use a modal alone.
He may not. The surgeon might operate first.
Does the patient have a broken bone?
Does he need a cast?
He has to. He was in a serious accident.

12. Be Careful! Use be in short answers to questions that include be.
Oh wait. It has to be. I see the brain stem.
Could that be an image of my brain?
I’m not sure. It might be.

13. Could that X-ray be a knee?
Ask and answer questions about the X-rays. Use short answers.
Practice 3
Possible Questions
Could X-ray # ___ be a ___?
Can X-ray #___ be a ___?
Possible Answers
It has to be./It’s got to be.
It may/might/could be.
Could that X-ray be a knee?
It might be. 1. 2.
Example:
knee
shoulder
brain

14. References
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