English Modal Verbs
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 Modal forms
 Can
 Could
 Had Better
 Have to
 Have Got to
 May
 Might
 Must
 Ought to
 Shall
 Should
 Will
 Would

Modal Forms
Modal verbs can be used in a variety of different forms. Study the examples below.
Modal Simple
I could swim at the beach.
Modal Continuous
I could be swimming at the beach right now.
Modal Perfect
I could have swum at the beach yesterday.
Modal Perfect Continuous
I could have been swimming at the beach
instead of working in the office.
Passive Modal Simple
The room should be cleaned once a day.
Passive Modal Continuous

2. SHIFT TO "COULD"
I could speak Chinese
when I was a kid.
1. I can't speak Swahili.
2. SHIFT TO "COULD"
I couldn't speak Swahili.
be able to
3. SHIFT TO "BE ABLE
TO"
I will be able to speak
Chinese by the time I
finish my course.
3. SHIFT TO "BE ABLE
TO"
I won't be able to speak
Swahili.
can
ability during a
specific event
1. With a burst of
adrenaline, people can
pick up cars.
2. SHIFT TO "BE ABLE
TO"
With a sudden burst of
adrenaline, he was able to
lift the car off the child's
leg.
3. SHIFT TO "BE ABLE
TO"

1. I don't have any time. I
can't help her now.
2. SHIFT TO "BE ABLE
TO"
I didn't have time
yesterday. I wasn't able to
help her at that time.
3. I won't have any time
later. I can't help her then.
be able to
can
permission
1. I can drive Susan's car
when she is out of town.
2. SHIFT TO "BE
ALLOWED TO "
I was allowed to drive
Susan's car while she was
out of town last week.
3. I can drive Susan's car
while she is out of town
next week.
1. I can't drive Susan's car
when she is out of town.
2. SHIFT TO "BE
ALLOWED TO "
I wasn't allowed to drive
Susan's car while she was
out of town last week.
3. I can't drive Susan's car

dollar or two.
You can't be 45! I thought
you were about 18 years
old.
This use is usually a
generalization or a
supposition.
could
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Could
"Could" is used to express possibility or past ability as well as to make suggestions and requests.
"Could" is also commonly used in conditional sentences as the conditional form of "can."
Examples:
• Extreme rain could cause the river to flood the city. possibility
• Nancy could ski like a pro by the age of 11. past ability
• You could see a movie or go out to dinner. suggestion
• Could I use your computer to email my boss? request
• We could go on the trip if I didn't have to work this weekend. conditional
Using "Could" in Present, Past, and Future
Most modal verbs behave quite irregularly in the past and the future. Study the chart below to
learn how "could" behaves in different contexts.
Modal Use
Positive Forms
1. = Present 2. = Past 3. =
Future
Negative Forms
1. = Present 2. = Past 3. =
Future
You can
also use:

the world.
could
suggestion
1. NO PRESENT FORM
2. You could have spent your
vacation in Hawaii.
3. You could spend your
vacation in Hawaii.
NO NEGATIVE FORMS
could
past ability
I could run ten miles in my
twenties.
I could speak Chinese when I
was a kid.
"Could" cannot be used in
positive sentences in which you
describe a momentary or one-
time ability.
Yesterday, I could lift the couch
by myself. Not Correct
I couldn't run more than a mile in
my twenties.
I couldn't speak Swahili.
"Could" can be used in negative
sentences in which you describe
a momentary or one-time ability.
Yesterday, I couldn't lift the
couch by myself. Correct
be able to

Using "Had Better" in Present, Past, and Future
Most modal verbs behave quite irregularly in the past and the future. Study the chart below to
learn how "had better" behaves in different contexts.
Use
Positive Forms
1. = Present 2. = Past 3. =
Future
Negative Forms
1. = Present 2. = Past 3. =
Future
You can
also use:
had better
recommendation
1. SHIFT TO "SHOULD"
OR "OUGHT TO"
People should unplug toasters
before they clean them.
2. SHIFT TO "SHOULD
HAVE" OR "OUGHT TO
HAVE"
You should have unplugged
the toaster before you tried to
clean it.
3. You had better unplug the
toaster before you try to clean
1. SHIFT TO "SHOULD"
OR "OUGHT TO"
People shouldn't clean
toasters without unplugging

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Have To
"Have to" is used to express certainty, necessity, and obligation.
Examples:
• This answer has to be correct. certainty
• The soup has to be stirred continuously to prevent burning. necessity
• They have to leave early. obligation
Using "Have to" in Present, Past, and Future
"Have to" behaves quite irregularly in the past and the future. Study the chart below to learn how
"have to" behaves in different contexts.
Use
Positive Forms
1. = Present 2. = Past 3. =
Future
Negative Forms
1. = Present 2. = Past 3. = Future
You
can
also
use:
have to
certainty
1. That has to be Jerry. They
said he was tall with bright red
hair.
2. That has to have been the
right restaurant. There were no
other restaurants on the street.
1. SHIFT TO "MUST"
That must not be Jerry. They said he