Introducing
Your new presentation assistant.
Refine, enhance, and tailor your content, source relevant images, and edit visuals quicker than ever before.
Trending searches
Modals of obligation
Modals
Modals don't take "s" with he, she, or it.
She must do her homework.
You use "not" to make modals negative.
We should not be late.
Modals are followed by the infinitive of the verb,
I should eat lunch now.
and can't be used in the past or future.
NOT CORRECT: Yesterday, I must go to class.
but some verbs work like modals,
have to/has to need to/needs to
and they are followed by to+infinitive,
She has to ask her father.
and they can be used in the past and future.
Yesterday, I had to go to class.
has to --> had to, will have to
needs to --> needed to, will need to
"Ought" works like a modal (no past or future)
but it always has "to" with it.
You ought to memorize these rules.
General Rules
NO!!!
RULES
We don't use "must not" in the past.
Instead, we use different words.
Example:
It was not allowed.
People couldn't do it.
NO
RULES
We use "had better not" to give specific advice.
We use it when something bad will probably happen
if we don't follow the advice.
We don't use "had better not" in the past.
no
RULES
We use "shouldn't" to give general or specific advice.
We use it to say the something is a bad idea.
We don't use "shouldn't" in the past.
maybe
RULES
We use "don't/doesn't have to" or "don't/doesn't need to"
to say something is not necessary.
There is a choice: yes or no.
Also, you can use these in the past:
"didn't have to" or "didn't need to"
We use "could" to say something is possible.
There is a choice: yes or no.
yes
RULES
We use "should" or "ought to" to say something is a good idea.
We can use it for general advice or specific advice.
We don't use "should" or "ought to" in the past.
"Ought to" always uses "to" before the infinitive verb.
YES
RULES
We use "had better" to say that something is a good idea.
We usually use it for specific advice.
We often use it when something BAD will probably happen
if we don't follow the advice.
YES!!!
RULES
We use "must" "have to/has to" and "need to/needs to" to say something is necessary.
There is no choice.
We can use "have to/has to" and "need to/needs to" in the past: "had to" or "needed to."
We can't use "must" in the past.
must
have to/has to
need to/needs to
had better
ought to
should
don't need to
doesn't need to
don't have to
doesn't have to
could
shouldn't
had better not
must not
Modals
Practice
have to
don't have to
must
mustn't
have to
don't have to
must
mustn't
should
shouldn't
have to
don't have to
all modals
For practice, follow the links in each section.
They will take you to an explanation or a quiz.
Use the "all modals" links to practice everything altogether.
of obligation
Some say "no."
but some say "yes."
Some say "maybe."
We use modals of obligation to give advice.
of obligation
How strong are they?
Some are very strong,
but some are not.
must
had better not
has to / have to
had better
Some examples?
ought to
don't need to / doesn't need to
need to / needs to
must not
could
shouldn't
should
doesn't have to / don't have to
VERY STRONG!!
not too strong
VERY STRONG!!
strong
not too strong
strong
Fish have to be in water to survive.
Travelers must show their passports.
You had better stay back from the cliff.
You don't want to fall.
You had better not put that in your mouth!
You don't have to drink coffee.
OR
You don't need to drink coffee.
You could drink tea.
Plants need to have sunlight to live.
Children
must not
shout at
their parents.
You must not smoke here.
She shouldn't procrastinate.
You had better not let him eat that!
She shouldn't
wait until the
last minute.
You must not run with scissors.
She ought to go to sleep earlier!
We don't need to take the stairs. OR We don't have to take the stairs.
We could take the elevator.
need to/needs to
You should brush your teeth after every meal.
You shouldn't slouch!
Someone had better put her to bed.
She looks like she's going to fall down!
She shouldn't wear those shoes when she has to walk a lot.
You
must not
steal!
could
She shouldn't eat all that food.
He had better hurry
if he doesn't want to be late.
Drivers must obey the laws.
There are children in the street.
You had better drive slowly.
You should be quiet
in the library.
He had better not
touch that hot stove!
You don't have to tell me now.
You can tell me later.
ought to
must
doesn't have to
don't have to
doesn't need to
don't need to
You had better not
knock on this door.
We don't need to drive to the mall. We could take the Metro.
I had better slow down around this corner.
It looks dangerous.
has to/have to
should
shouldn't
must not
had better not
had better
She ought to study harder.
You must be 18 years old to drive.
If you're younger than 18, the police can stop you!
You had better turn down your music
or the neighbors will start complaining!
Students don't need to bring their passports to school.
I really shouldn't eat so much cake.
It's got too much sugar, so it's not healthy.
You should buy that dress!
The color is perfect.
You must not smoke inside the school.
It is against the law.
You had better not lie to your parents!
If you do, they'll punish you.
Students must be on time for class.
If they are late, they will be marked absent.
I'd better wash my hands before I eat.
I think they're a bit dirty.
Students must not use their cell phones in class.
If they do, the teacher will take them.
You don't have to help me.
I'm OK.
You shouldn't buy that dress.
It's too expensive.
I had better not go to bed late tonight.
I have a test tomorrow.
Everyone ought to eat a healthy diet.
If you want a good grade, you need to study.
We had better feed the cat.
She's really hungry!
Parents don't need to pay for public school.
It's free.
People shouldn't smoke because it causes cancer.
I ought to read more.
That would really help my English.
People must not steal.
I had better not forget to call my friend on her birthday.
If I forget, she'll cry.
I must not forget to study!
There's a test tomorrow!
Fatima has to visit her grandmother this weekend.
Her father told her to do that.
You had better pay attention in class,
or you'll miss something important.
Your sister shouldn't play video games all night.
She looks really tired today.
We don't have to come to school on Saturday.
It's our day off.
You should always tell the truth.
You had better not leave your handbag on the table.
Someone might take it!