1. UNIT 3
MODALS: SHOULD, MUST, HAVE TO
All the modal verbs are used as auxiliaries and all of them form conjugations in the same way
(Todos los verbos modales son usados como auxiliares y todos ellos forman conjugaciones en la
misma forma)
The auxiliary verbs must, should, and have to modify the meaning of the main verb expressing
ability, authority, formality, politeness.
SHOULD: It is used for giving advice (Es usado para dar consejo)
MUST: It expresses strong obligation. It depends on the person speaking (Expresa fuerte
obligación. Depende de la persona que habla). Commonly used in writing
HAVE TO: It expresses obligation and it is the most common expression in everyday use. (Expresa
obligación y es la expression más común de uso diario)
SUBJECT-PRONOUN AFFIRMATIVE NEGATIVE QUESTION
I Must Must not (mustn’t) Must I, we, you,
We Should should not (shouldn’t) they_____?
You have to don’t have to Should I, we, you,
They they_____?
Sara and Jhon Do I, we, you, they
have to _____?
She Must Must not (mustn’t) Must he, she it _____?
He Should should not (shouldn’t) Should he, she, it ___?
It Has to doesn’t have to Does he, she, it have
Jenny to _____?
Note: we usually use have to in questions not must. Ex: what do I have to do? (Qué debo/tengo
qué hacer?)
EXAMPLES:
My mother should lose weight (Mi mamá debería perder peso)
She shouldn’t eat fast food (ella no debería comer comida rápida)
Should they go to the dentist? (Ellos deberían ir al odontólogo?)
He must be more disciplined (El debe ser más disciplinado)
We mustn’t smoke (No debemos fumar)
Must you see him? (tu debes verlo?)
I have to take a bath everyday (Tengo que tomar un baño todos los dias)
She has to get up early (Ella se tiene que levantar temprano)
We don’t have to go to school on Sunday (No tenemos que ir al colegio el domingo)
Do they have to pray every day? (Tienes que rezar todos los días?)
Does it have to sleep in the garden? (Tiene que dormir en el jardín?)

2. HEALTHY HABITS: (Hábitos saludables)
To get a physical or medical check up twice a year
To eat a varied and balanced diet
To avoid a sedentary life
To sleep eight hours a day
To exercise
To have three meals a day
To avoid eating too much candy and soda
UNHEALTHY HABITS: (Hábitos no saludables)
To have a sedentary life
To eat fattening food. (junk food)
To consume drugs
To sleep less than 6 hours
To sleep too much
EXERCISE: Write some of the obligations a model needs to follow in order to keep in fit. Use must,
mustn’t, have to, don’t have to, (doesn’t have to)
She/He has to sleep eight hours a day________________________
He/she mustn’t consume any drugs__________________________
_______________________________________________________
_______________________________________________________
_______________________________________________________
_______________________________________________________
_______________________________________________________
EXERCISE: According to the pictures tell them what to do? Use should, shouldn’t, must, mustn’t,
has/have to, does/doesn’t have to depending on the situation.

3. ARE YOU HEALTHY?
EXERCISE: Answer this survey and check your health habits:

4. 1. Do you like working out? (exercising)
a. Yes
b. No
2. How often do you do it? 5. Do you eat vegetables?
a. Once a week a. Yes
b. Twice a week b. No
c. Three times a week 6. Do you take vitamins?
d. More a. Yes
3. What kind of exercise do you do? b. No
a. Swimming c. Sometimes
b. Aerobics 7. How many hours do you sleep?
c. Walking, jogging a. Less than five
d. Weight lifting b. Between six and eight
e. Yoga c. More than eight
f. Soccer 8. How often do you have a physical check
g. Other up?
4. How many meals do you have a day? a. Once a year
a. One b. Twice a year
b. Two c. Occasionally
c. Three d. Never
d. Four
YOUR SCORE
1. a. 3 b. 0 19 - 26: Congratulations¡ you are a very healthy person.
You should keep it up.
2. a. 1 b. 2 c. 3 d. 4
3. Any answer is worth 3 points. 11 - 18: Good health but you should care more about
sports and your diet.
4. a. 1 b. 2 c. 3 d. 4
5. a. 3 b. 0 0 - 10: you must go to the doctor. You must pay
attention to all your health habits.
6. a. 3 b. 0 c.2
7. a. 1 b. 3 c. 1
8. a. 2 b. 3 c. 1 d. 0
EXERCISE: Complete the sentences to express obligation or advice. Use must, mustn’t, has/have
to, don’t/doesn’t have, should, shouldn’t.

5. 1. we ____________ pollute the planet
2. my mother ___________ cook everyday
3. you ____________ bathe the dog once a month
4. you __________ wear the uniform
5. we ______________ throw litter on the streets
6. you _____________ run in the classroom
7. we _____________ brush our teeth three times a day
8. the children ______________ cook their food
9. you _______________ disobey the school rules
10. The students ____________ pay attention in class
11. You _______________ do your homework
12. You ____________ do more exercise
13. My brother ______________ keep his room tidy
14. We _______________ smoke
15. You ______________ get late to school
16. We ____________ eat junk food.
17. My father ____________ get up early everyday
18. You _____________ avoid a sedentary life
IMPERATIVES
Use imperatives to give and follow instructions. (utilice imperactivos para dar y seguir
instrucciones)
EXAMPLES:
Please, speak slowly
Don’t answer the pone
Open the door
Stand up, please
Please, write clearly
Don’t play music so loudly
Turn the page