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How to use the verb tenses and Modals Auxiliaries.
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Verb Tenses
The Present Simple Tense
(also called the simple present tense)
Simple present tense with 'be'
The verb 'be' is different from the other verbs in this tense. Let's look at 'be' first:
Here's the positive form (positive means a normal sentence, not a negative or a
question. This is sometimes called 'affirmative')
Positive Positive Short Form
I am I'm
you are you're
he is he's
she is she's
it is it's
we are we're
they are they're
Next, here's the negative. It's very easy. You only add 'not'.
Negative Negative short form
I am not I'm not
you are not you aren't
he is not he isn't
she is not she isn't
it is not it isn't
we are not we aren't
they are not they aren't
And finally let's talk about the question form of the present simple with 'be'.
Firstly, here's the 'yes / no' question form:
Yes / No Questions
am I ?
are you ?
is he ?
is she ?
is it ?
are we ?
are they ?
If you'd like to make a 'wh' question, you just put the question word at the front:
Wh Questions
where am I ?
what are you ?
why is he ?
who is she ?
when are we ?
how are they ?
Present simple tense with other verbs
With all other verbs, we make the present simple in the same way.
The positive is really easy. It's just the verb with an extra 's' if the subject is 'he', 'she',
or 'it'. Let's take the verb 'play' as an example:
Positive (of 'play')
I play
you play
he plays
she plays
it plays
we play
they play
To make the negative form, you need to use 'do not' (don't) or ' does not' (doesn't).
Negative (of 'play')
I do not play I don't play
you do not play you don't play
he does not play he doesn't play
she does not play she doesn't play
it does not play it doesn't play
we do not play we don't play
they do not play they don't play
How about the question form of the present simple tense?
We use 'do' or 'does' before the subject to make the 'yes / no' question:
Yes / No questions
do I play ?
do you play ?
does he play ?
does she play ?
does it play ?
do we play ?
do they play ?
Just like with 'be', if you'd like to make a 'wh' question, you just put the question word
at the front:
Wh Questions
where do I play ?
what do you play ?
why does he play ?
who does she play ?
when do we play ?
how do they play ?
Uses:
1: First, we use the Present Simple when something is generally true:
The sun rises in the east.
People need food.
It snows in winter.
2: We also need to use this tense for a situation that we think is more or less
permanent
Where do you live?
She works in a bank.
They love coffee.
3: The next use is for habits or things that we do regularly. We often use adverbs of
frequency in this case
Do you smoke?
I play tennis every Tuesday.
We often go to the cinema.
She gets up at seven o'clock every day.
4: Four, we use the simple present to talk about what happens in books, plays, or films:
The hero dies at the end of the film.
A young woman travels through Europe, where she meets different people,
and finally falls in love.
In this book, an army invades Britain.
5: We use it in the first and the zero conditionals:
If it rains, I won't come.
If you heat water to 100 degrees, it boils.
6: Strangely, we can use this tense to talk about the future. When you are discussing a
timetable or a fixed plan, you can use this tense.
School begins at nine tomorrow.
Our train leaves at eleven.
What time does the film start?
7: We also use it to talk about the future after words like ' 'when', 'until', 'after',
'before' and 'as soon as' in a future sentence:
I will call you when I have time. (Not: 'will have')
I won't go out until it stops raining.
She'll come as soon as her babysitter arrives.
8: We need to use this simple tense with stative verbs (verbs which we don't use in
continuous tenses), in situations where we'd usually use the present continuous:
This soup tastes great.
You look fabulous.
I think she is very pretty.
How to make the Present Continuous Tense
(also called the Present Progressive Tense)
The present continuous (sometimes called the present progressive) tense in English is
really easy to make and is the same for all verbs. We make it using the present simple
of 'be' + verb-ing:
Here is how we make the positive:
Positive Positive Short Form
I am sleeping I'm sleeping
you are sleeping you're sleeping
he is sleeping he's sleeping
she is sleeping she's sleeping
it is sleeping it's sleeping
we are sleeping we're sleeping
they are sleeping they're sleeping
We can make the negative by adding 'not':
Negative Negative Short Form
I am not sleeping I'm not sleeping
you are not playing you aren't playing
he is not reading he isn't reading
she is not working she isn't working
it is not raining it isn't raining
we are not cooking we aren't cooking
they are not listening they aren't listening
Questions are also really, really easy. Just like we made the question with 'be' in the
present simple, here we also put 'am', 'is', or 'are' before the subject to make a 'yes /
no' question:
Yes / No Questions
am I eating chocolate ?
are you studying now ?
is he working ?
is she doing her homework ?
is it raining ?
are we meeting at six ?
are they coming ?
For 'wh' questions, just put the question word at the front:
Wh Questions
Why am I eating chocolate ?
What are you studying now ?
When is he working ?
What is she doing ?
Why is it raining ?
Who are we meeting ?
How are they travelling ?
Uses:
1: First, we use it for things that are happening at the moment of speaking.
I'm working at the moment.
Please call back as– we are eating dinner now.
Julie is sleeping.
2: We can also use this tense for temporary situations, when we feel something won't
continue for a long time.
She's staying with her friend for a week.
I'm living in London for a few months.
John's working in a bar until he finds a job in his field.
3: We can use the present continuous for habits but they have to be temporary or new
habits
He's eating a lot these days.
She's swimming every morning (she didn't use to do this).
You're smoking too much.
4: Another present continuous use is for annoying habits, when we want to show that
something happens too often and we don't like it. In this case we usually use an adverb
like 'always', 'forever' or 'constantly'.
You're always losing your keys!
She's constantly missing the train.
He's always sleeping in.
5: The next use is for definite future arrangements (with a future time word). In this
case we have already made a plan and we are pretty sure that the event will happen in
the future.
I'm meeting my father tomorrow.
We're going to the beach at the weekend.
I'm leaving at three.
6: Finally we use this tense to talk about a situation which is slowly changing.
I'm getting better at playing the piano.
The weather is improving.
The Present Perfect Simple Tense
To make the positive present perfect tense, use:
'have' / 'has' + the past participle
Make the past participle by adding 'ed' to regular verbs (for example, 'play'
becomes 'played')
There are a few verbs that change their spelling when you add 'ed' (for
example, 'study' becomes 'studied')
Positive Positive Short Form
I have played I've played
you have worked you've worked
he has written he's written
she has walked she's walked
it has rained it's rained
we have travelled we've travelled
they have studied they've studied
The negative is really simple too. Just put 'not' after 'have' or 'has':
Negative Negative Short Form
I have not eaten breakfast today I haven't eaten
you have not been to Asia you haven't been
he has not seen the new film he hasn't seen
she has not played tennis she hasn't played
it has not snowed this winter it hasn't snowed
we have not slept all night we haven't slept
they have not tried the food they haven't tried
To make a question, put 'have' or 'has' in front of the subject:
Yes / No' Questions
have I missed the bus?
have you visited London?
has he worked as a waiter before?
has she met John?
has it been cold this week?
have we arrived too early?
have they studied English grammar before?
As you can imagine, for 'wh' questions, we just put the question word before 'have' or
'has':
'Wh' Questions
where have I left my umbrella?
what have you done today?
why has he gone already?
where has she been in the UK?
why has it rained so much this summer?
what have we done?
where have they learned English before?
Uses:
1: Life experience
(we don't say when the experience happened, just sometime in the past)
I have been to Tokyo.
She has lived in Germany.
They have visited Paris three times.
2: A finished action with a result in the present (focus on result)
I've lost my keys (so I can't get into my house).
She's hurt her leg (so she can't play tennis today).
They've missed the bus (so they will be late).
3: With an unfinished time word (this month, this week, today, in the last year)
I haven't seen her this month.
She's drunk three cups of coffee today.
This week they've been shopping four times.
The present perfect continuous tense
(also called the present perfect progressive)
Here's the positive (it's the present perfect of 'be' + verb -ing):
Positive Positive Short Form
I have been walking I've been walking
you have been running you've been running
he has been cooking he's been cooking
she has been swimming she's been swimming
it has been raining it's been raining
we have been studying we've been studying
they have been sleeping they've been sleeping
To make the negative, just add 'not':
Negative Negative Short Form
I have not been walking I haven't been walking
you have not been running you haven't been running
he has not been cooking he hasn't been cooking
She has not been swimming she hasn't been swimming
it has not been raining it hasn't been raining
we have not been studying we haven't been studying
they have not been sleeping they haven't been sleeping
Can you guess how to make the question form of the present perfect continuous? It's
not very difficult - just put 'have' or 'has' before the subject:
'Yes / No' Questions
have I been walking?
have you been running?
has he been cooking?
has she been swimming?
has it been raining?
have we been studying?
have they been sleeping?
For 'wh' questions put the question word first:
'Yes / No' Questions
what have I been doing?
where have you been running?
what has he been studying?
why has she been working today?
how long has it been raining?
how long have we been watching this film?
how long have they been living here?
Uses:
1: To say how long for unfinished actions which started in the past and continue to the
present. We often use this with for and since.
I've been living in London for two years.
She's been working here since 2004.
We've been waiting for the bus for hours.
2: Actions which have just stopped (though the whole action can be unfinished) and
have a result, which we can often see, hear, or feel, in the present (focus on action).
I'm so tired, I've been studying.
I've been running, so I'm really hot.
It's been raining, the pavement is wet.
The Past Simple Tense
(also called the simple past tense)
It's similar to the present simple because it has different rules for the verb 'be', which
becomes 'was' or 'were':
The Past Simple with 'be'
Here's how to make the positive:
Positive with 'be'
I was cold
you were tired
he was in the garden
she was late
it was sunny
we were on holiday
they were hungry
To make the negative with 'be', just add 'not':
Negative with 'be' Negative Short Form
I was not sleepy I wasn't sleepy
you were not on the
bus you weren't on the bus
he was not at school he wasn't at school
she was not beautiful she wasn't beautiful
it was not cold it wasn't cold
we were not at work we weren't at work
they were not tired they weren't tired
To make a question, just like the present simple, we change the position of 'was /
were' and the subject.
Here are the past simple 'yes / no' questions with 'be':
'Yes / No' Questions with 'Be'
was I sleepy?
were you late?
was he at the cinema?
was she kind?
was it hot?
were we hungry?
were they at work?
And the 'wh' questions with 'be' (the question word just goes at the beginning,
everything else is the same):
'Wh' Questions with 'Be'
why was I sleepy?
where were you?
when was he at the cinema?
how was she?
how was it?
why were we hungry?
when were they at work?
The Past Simple (Simple Past) with Other Verbs
Positive with Other Verbs
I walked (regular)
you played (regular)
he cooked (regular)
she listened (regular)
it rained (regular)
we ate (irregular)
they drank (irregular)
In the negative there aren't any irregular verbs. All verbs use 'did not (didn't) +
infinitive':
Negative Negative Short Form
I did not walk I didn't walk
you did not play you didn't play
he did not cook he didn't cook
she did not listen she didn't listen
it did not rain it didn't rain
we did not eat we didn't eat
they did not drink they didn't drink
Questions are also very easy. Just put 'did' before the subject, and the infinitive after it.
Here are the 'yes / no' questions:
'Yes / No' Questions
did I walk?
did you play?
did he cook?
did she listen?
did it rain?
did we eat?
did they drink?
To make a 'wh' question, of course, put the question word at the beginning of the
sentence:
'Wh' Questions
where did I go?
what did you play?
what did he cook?
why did she listen?
when did it rain?
where did we eat?
how did they travel?
Here's when we use it:
1: Finished events in the past with no connection to the present:
Leonardo painted the Mona Lisa.
The Vikings invaded Britain.
2: With a finished time word (yesterday, last week, at 2 o'clock, in 2003):
I went to the cinema yesterday.
We visited Japan in 2007.
3: For stories / lists of events:
He went to a café, sat down and lit a cigarette.
Yesterday I went to the library, met a friend for lunch, and played tennis.
4: Details of news:
I've hurt my leg. I fell off a ladder when I was painting my bedroom.
I've been on holiday. I went to Spain and Portugal.
5: As part of the second conditional:
If I won the lottery, I would buy a house in Chelsea.
If she knew his number, she would call him.
The Past Continuous
(or past progressive tense)
How can we make the past continuous? Firstly, check that you know how to make the
past simple with 'be' (subject + was / were). Then just add verb-ing.
Here's the positive form:
I was sleeping
you were working
he was coming
she was reading 'War and Peace'
it was raining
we were shopping
they were watching a film
Next, here's the negative - it's very easy, just add 'not':
I was not (wasn't) sleeping
you were not (weren't) working
he was not (wasn't) coming
she was not (wasn't) reading 'War and Peace'
it was not (wasn't) raining
we were not (weren't) shopping
they were not (weren't) watching a film
And, just like the past simple with 'be', to make a 'yes / no' question, put 'was / were'
in front of the subject:
Was I listening?
Were you working?
Was she working?
Was he living in Paris at the time?
Was it snowing when you arrived?
Were we eating?
Were they studying?
To make a 'wh' question (of course) put the question word at the beginning:
Why was I working?
Where were you living?
How was she travelling?
Where was he going?
Why was it snowing in the summer?
What were we eating?
Why were they studying?
Uses:
1: A continuous action in the past which is interrupted by another action or a time:
I was taking a bath when the telephone rang.
At three o'clock, I was working.
2: Background information, to give atmosphere to a story:
It was a beautiful day. The birds were singing, the sun was shining and in the
cafes people were laughing and chatting.
3: An annoying and repeated action in the past, usually with 'always':
He was always leaving the tap running.
4: For two actions which happened at the same time in the past:
I was watching TV and he was reading.
The Past Perfect Tense
The positive - make it with 'had' + the past participle (usually made by adding 'ed' to
the infinitive, but a few verbs have irregular past participles):
I had been (I'd been)
You had gone (you'd gone)
She had met (she'd met)
He had played (he'd played)
It had rained (it'd rained)
We had bought (we'd bought)
They had studied (they'd studied)
The short form for 'had' is 'd.
(Be careful not to confuse it with 'would'. Would is followed by the infinitive - 'I'd go',
whereas had is followed by the past participle - 'I'd gone').
For the negative just add 'not':
I had not been (I hadn't been)
You had not gone (you hadn't gone)
She had not met (she hadn't met)
He had not played (he hadn't played)
It had not rained (it hadn't rained)
We had not bought (we hadn't bought)
They had not studied (they hadn't studied)
And to make a 'yes / no' question put 'had' before the subject:
Had I come?
Had you eaten?
Had she gone?
Had it rained?
Had he studied?
Had we met?
Had they left?
For 'wh' questions put the question word at the beginning:
When had I come?
Why had you eaten?
Where had she gone?
When had it rained?
Why had he studied?
How had we met?
When had they left?
Uses:
1: A completed action before something else in the past.
When we arrived, the film had started.
2: To explain or give a reason for something in the past.
I'd eaten dinner so I wasn't hungry.
It had snowed in the night, so the bus didn't arrive.
3: Stative verbs only: something that started in the past and continued up to another
action in the past.
When he graduated, he had been in London for six years.
4: As part of the third conditional.
If I had known you were ill, I would have visited you.
The Past Perfect Continuous
Here's how to make the past perfect continuous. It's 'had' + been (the past participle of
'be')+ verb-ing
Firstly, let's look at the positive form:
I had been living
You had been going
She had been sleeping
He had been working
Next, the negative form:
I had not been trying (I hadn't been..)
You had not been working (you hadn't been..)
She had not been crying (she hadn't been..)
He had not been shopping (he hadn't been..)
It had not been snowing (it hadn't been..)
We had not been reading (we hadn't been..)
They had not been running (they hadn't been..)
It's pretty easy to make the question too.
'Yes / no' questions:
Had I been working?
Had you been sleeping?
Had she been reading?
Had he been watching TV?
Had it been raining?
Had we been drinking?
Had they been eating?
'Wh' questions:
Where had I been working?
How long had you been sleeping?
What had she been reading?
How long had he been watching TV?
How long had it been raining?
What had we been drinking?
Why had they been eating?
Uses:
1: Something that started in the past and continued up to another action or event
(tells us 'how long')
She had been working at that company for a year when she met James.
2: Cause of something in the past
The pavement was wet, it had been raining.
The Simple Future Tense
(or future with will)
Here's the positive form (it's just 'will' + infinitive):
I will meet him later (I'll ..)
You will come (you'll..)
It will rain tomorrow (it'll)
She will be late (she'll..)
He will help us later (he'll..)
We will get married in September (we'll)
They will cook dinner (they'll..)
Next, here's the negative form (just add 'not' - remember will not = won't):
I will not go (I won't ..)
You will not be late (you won't ..)
It will not snow tomorrow (it won't..)
She will not get the job (she won't..)
He will not pass the exam (he won't ..)
We will not come (we won't..)
They will not stop (they won't ..)
Finally, here's the question:
'yes / no' questions:
Will I go?
Will you come early?
Will it be cold?
Will she dance?
Will he arrive soon?
Will we cook?
Will they leave?
'wh' questions:
Where will I go?
Why will you come early?
When will it be cold?
Who will she dance with?
What time will he arrive?
What will we cook?
When will they leave?
Uses:
1: A decision at the moment of speaking:
A: 'I'm cold'.
B: 'I'll close the window'.
2: Prediction based on opinion:
I think the Conservatives will win the next election.
3: A future fact:
The sun will rise at 7am.
4: Promises / requests / refusal / willingness:
I'll help you with your homework.
Will you give me a hand?
I will give up smoking!
5: In the same way as the future continuous, but with state verbs:
I'll be at the station when you arrive.
We use 'be going to' + infinitive for:
1: Future plans made before the moment of speaking:
A: 'We've run out of milk.'
B: 'I know, I'm going to buy some.'
2: Prediction based on present evidence:
Look at those boys playing football! They're going to break the window.
The Future Continuous
(or future progressive tense)
Here's how to make it:
The positive (will + be + verb-ing):
I will be sleeping
you will be working
she will be studying
it will be raining
he will be cooking
we will be eating breakfast
they will be travelling
Here's the negative:
When John gets home,
I will not be working (I won't be ..)
you will not be reading (you won't be ..)
he will not be cooking (he won't be ..)
she will not be studying (she won't be ..)
it will not be snowing (it won't be ..)
we will not be watching TV (we won't be ..)
they will not be sleeping (they won't be ..)
Next, the question:
'yes / no' questions:
will I be cooking?
will you be dancing?
will she be singing?
will he be eating?
will we be drinking?
will it be snowing?
will they be talking?
'wh' questions:
what will I be doing?
where will you be working?
how will she be travelling?
what will he be eating?
why will we be studying?
why will it be snowing?
what will they be wearing?
Uses:
1: A continuous action in the future which is interrupted by a time or by another
action.
I’'ll be waiting when you arrive.
At eight o’clock, I’'ll be eating dinner.
2: A complete action in the future that will happen in the normal course of events.
The Government will be making a statement later.
Will you be taking your car to the meeting?
3: To make a guess about the present.
My mother will be working now
The future perfect is made with the future simple of 'have' (will have) and the past
participle. For regular past participles add 'ed' to the verb ('play' becomes 'played').
Here's the positive:
By six pm tonight:
I will have finished this book
You will have studied the English tenses
She will have cooked dinner
He will have arrived
We will have met Julie
It will have stopped raining
They will have left Japan
Here's the negative:
I will not have finished this book
You will not have studied the English tenses
She will not have cooked dinner
He will not have arrived
We will not have met Julie
It will not have stopped raining
They will not have left Japan
To make the question, just put 'will' before the subject:
'Yes / no' questions:
will I have finished writing this book?
will you have studied all the English verb tenses?
will she have graduated?
will he have got married?
will it have got colder?
will we have met your boyfriend?
will they have left their jobs?
'Wh' questions:
When will I have finished writing this book?
Why will you have studied all the English verb tenses by tomorrow?
When will she have been here three weeks?
Why will he have got married before June?
Why will it have got colder by May?
How will we have met your boyfriend by tonight?
When will they have left their jobs?
Uses:
1: With a future time word, (and often with 'by') to talk about an action that will finish
before a certain time in the future, but we don't know exactly when.
By 10 o'clock I will have finished my homework.
By the time I'm sixty, I will have retired.
The Future Perfect Continuous Tense
(also called the future perfect progressive)
Positive Form Positive Short Form
I will have been working I'll have been working
You will have
been sleeping
You'll have
been sleeping
She will have
been studying
She'll have
been studying
He will have
been cooking
He'll have
been cooking
It will have been raining It'll have been raining
We will have
been exercising
We'll have
been exercising
They will have
been travelling
They'll have
been travelling
Negative Form Negative Short Form
I will not have
been working
I won't have
been working
You will not have
been sleeping
You won't have
been sleeping
She will not have
been studying
She won't have
been studying
He will not have
been cooking
He won't have
been cooking
It will not have
been raining
It won't have
been raining
We will not have
been exercising
We won't have
been exercising
They will not have
been travelling
They won't have
been travelling
'Yes / No' Questions
Will I have been working?
Will you have been sleeping?
Will she have been studying?
Will he have been cooking?
Will it have been raining?
Will we have been exercising?
Will they have been travelling?
'Wh' Questions
Where will I have been working?
Why will you have been sleeping?
Where will she have been studying?
What will he have been cooking?
How long will it have been raining?
Where will we have been exercising?
Uses:
1: With a time word, to talk about an action which starts before a time in the future
and continues up to that time.
In April 2009, I will have been teaching here for two years.
Modal Auxiliaries:
The modal auxiliaries (or modals) include the following:
can, could, may, might, must, should, will, would
Modals are always followed by the base form of a verb or auxiliary verb.
Modals are always the same form no matter what the subject is.
In standard American English, a predicate verb phrase cannot contain more than one
modal.
correct
He will be able to go.
not correct
He will can go.
Below are example sentences containing the modal may and the verb go. Notice that the form
of the modal does not change.
I may go.
You may go.
He may go.
It may go.
We may go.
They may go.
He may have gone.
They may have gone.
Modals and related verb phrases add meanings to verbs. Below are some of those meanings:
Ability/Availability
future: will be able to
present: can, am/is/are able to
past: could, was/were able to
Requests
present/future: can, could, will, would
Permission
future: will be allowed to
present/future: may, can, could, am/is/are allowed to
past: could, was/were allowed to
Possibility
present/future: may, might, could
past: may have, might have, could have
Impossibility
present/future: couldn’t, can’t
past: couldn’t have
Advisability
present/future: should, ought to, had better
past: should have, ought to have, had better have
Expectation
present/future: should, ought to
past: should have, ought to have
Necessity
future: will have to
present/future: must, have to, has to
past: had to
Lack of Necessity
future: won’t have to
present/future: don’t have to, doesn’t have to
past: didn’t have to
Prohibition
present/future: must not, may not, cannot
past: could not
Logical Deduction (=Probability)
present: must, have to, has to
past: must have, have to have, has to have
SOCIAL MODALS
The choice of modal depends partly on the social situation.
We often use formal language with strangers (people we don’t know) and superiors (people
with some power over us such as our employers, doctors, and teachers).
We often use informal language with our equals (our friends and family) and subordinates
(people we have some power over such as our employees or children).
General requests (present and/or future):
Will you help me? (Informal Are you willing?)
Would you help me (Formal Are you willing?)
Can you help me? (Informal Are you able?)
Could you help me (Formal Are you able?)
Requests for permission (present and/or future):
May I leave the room? (Formal)
Might I leave the room? (Formal rarely used)
Could I leave the room? (Less formal
Can I leave the room? (Informal)
Expressing suggestions, advice, warnings, necessity (present and/or future):
The choice of modal depends partly on the urgency of the message or the authority of the
speaker/writer or both.
Suggestions:
You could see the doctor.
You might see the doctor.
Advice:
You should see the doctor.
You ought to see the doctor.
Warning/strong advice:
You had better see the doctor.
Strong advice/necessity:
You have to see the doctor.
You have got to see the doctor.
You must see the doctor.
No choice:
You will see the doctor.
MODALS OF BELIEF (beliefs about present time)
The choice of modal depends partly on what the speaker or writer believes.
-Someone is knocking at the door:
That could be Fred.
That might be Fred.
= It’s possible. I’m less than 50% sure.
That may be Fred.
= It’s possible. I’m less than 60% sure.
That should be Fred.
That ought to be Fred.
= I’m expecting Fred and I think he’s here.
That must be Fred.
That has to be Fred.
That has got to be Fred.
= It’s probably Fred. I have a good reason to believe it is Fred.
That will be Fred.
= I believe it is Fred. I’m about 99% sure.
That can’t be Mary.
That couldn’t be Mary.
= It’s impossible. I’m about 99% sure.
That is Fred.
= I know it’s Fred. I’m 100% sure.
MODALS OF BELIEF (beliefs about past time)
The choice of modal depends partly on what the speaker or writer believes.
-Someone was knocking at the door:
That could have been Fred.
That might have been Fred.
= It’s possible. I’m less than 50% sure.
That may have been Fred.
= It’s possible. I’m less than 60% sure.
That must have been Fred.
That has to have been Fred.
That has got to have been Fred.
= It was probably Fred. I have a good reason to believe it was Fred.
That couldn’t have been Mary.
= It’s impossible. I’m about 99% sure.
That was Fred.
= I know it was Fred. I’m 100% sure.
MODALS OF BELIEF (beliefs about future time) The choice of modal depends partly on what
the speaker or writer believes.
-What will the weather be like tomorrow?
It could rain tomorrow.
It might rain tomorrow.
= It’s possible. I’m less than 50% sure.
It may rain tomorrow.
= It’s possible. I’m less than 60% sure.
It should rain tomorrow.
It ought to rain tomorrow.
= I expect it will rain.
It will rain tomorrow.
= I believe it is going to rain. I’m about 99% sure.
It couldn’t snow tomorrow.
= It’s impossible. I’m about 99% sure.