1. Three openers for the same purpose
Suppose, let’s say, and imagine can mean accept this situation for the sake of discussion. The speaker is not necessarily claiming that it exists. A question about consequences often follows, but a conclusion, request, or standalone invitation to imagine a scene is also possible.
The discussion has two parts: a condition—opener + clause—and a question about the consequence. Keep the condition brief and concrete and the question exploratory: what would…, how would…, who would…, would you…? The question turns a description of a hypothesis into an invitation to talk.
Suppose / Let's say / Imagine + clause → what / how / who would … ?
- clause —
- A construction with a verb, often with its own subject: when I arrived. A non-finite clause may leave the subject unspoken: to get home.
Suppose the university moved all lectures online — how would students stay in touch?
Suppose the university moved all lectures online — how would students stay in touch?
The condition uses the past simple; the question asks about the consequence for students.
Let's say a flat costs 150,000 euros and the mortgage rate is six per cent. Who could afford it?
Let's say a flat costs 150,000 euros and the mortgage rate is six per cent. Who could afford it?
Let's say works well with numbers, and the question opens up discussion.
Imagine the sea level rose by one metre overnight. Which cities would suffer first?
Imagine the sea level rose by one metre overnight. Which cities would suffer first?
Imagine addresses the listener and paints a picture.
Suppose a stranger offered you a job abroad tomorrow — what would you ask first?
Suppose a stranger offered you a job abroad tomorrow — what would you ask first?
Tomorrow occurs with the past simple: the form marks hypothetical distance, not past time.
Tense shows how the speaker presents the scenario
A remote hypothesis often uses the past simple: Suppose the city banned cars — what would happen? Banned does not necessarily refer to the past here. An open assumption can use the present: Suppose it rains tomorrow — what will we do?
Do not extend the restriction on will in an ordinary if-condition to every sentence after imagine or let’s say: these can introduce different kinds of assumptions, including predictions. In this lesson's remote-hypothesis pattern, choose the past simple and a question with would. Will or would in another pattern may change the meaning rather than automatically make the sentence incorrect.
A few details: for be in the first and third person singular, both were and was are possible, with were more formal: Suppose I were the manager. Use could rather than can for ability or possibility within a remote scenario. Form negatives normally: Suppose nobody came, Suppose we didn't agree.
opener + subject + Past Simple (imagined present or future) | present tense (open possibility)
- subject / S —
- The grammatical subject: who or what the clause is about; the verb agrees with it. In The book was written, the book is the subject, although someone else does the action.
Suppose the shop stayed open all night — who would shop there?
Suppose the shop stayed open all night — who would shop there?
The past simple in the condition and would in the question.
Imagine your landlord doubled the rent — how would you react?
Imagine your landlord doubled the rent — how would you react?
An imagined situation uses doubled in this pattern, not will double.
Suppose it rains on the day of the wedding — what will we do?
Suppose it rains on the day of the wedding — what will we do?
An open real possibility: present tense and will in the question.
Let's say the server went down at noon — would we lose any data?
Let's say the server went down at noon — would we lose any data?
Let's say also takes the past simple for an imagined situation.
Suppose we could not reach the client by phone — what would be our plan B?
Suppose we could not reach the client by phone — what would be our plan B?
Could expresses hypothetical ability or possibility, and could not its absence; would appears in the question.
3. An imagined past: past perfect and would have
To imagine that the past had turned out differently, use the past perfect in the condition and would have + past participle in a question about the consequence: Suppose the pilot had ignored the warning — what would have happened? This frame helps analyse decisions that can no longer be changed.
Use the past perfect for an alternative past. Yesterday or last year alone does not require it in every assumption: Suppose she left yesterday can be an open conjecture about a past event. If the alternative past condition has a present consequence, say Imagine we had never met — where would you be now?
Suppose / Imagine + subject + had + V3 → question with would have + V3 about a past consequence; or would + base form about a consequence now
- subject / S —
- The grammatical subject: who or what the clause is about; the verb agrees with it. In The book was written, the book is the subject, although someone else does the action.
- V1 / base form —
- The base verb without to: work, go, be.
- V3 / past participle —
- The third verb form: worked, gone, seen. Used after have/has or in the passive, for example; it is not always the same as V2.
Suppose the pilot had ignored the warning — what would have happened?
Suppose the pilot had ignored the warning — what would have happened?
The past perfect in the condition, and would have + V3 in the question.
Imagine we had never met — where would you be now?
Imagine we had never met — where would you be now?
An unrealised alternative past and a present consequence: would be.
Let's say they had paid in cash — would the bank have noticed?
Let's say they had paid in cash — would the bank have noticed?
Let's say also works with the past perfect.
4. Questions about consequences: would, could, should
The most typical question after a hypothetical condition uses would, turning the assumption into an invitation to reason. Could and might emphasise possibility, as in could we survive?, while should asks for a recommendation, as in what measures should the bank take? All remain within the imagined situation.
Use ordinary question word order: question word, modal verb, subject, verb. The error how we would attract occurs because that is indirect-question order. The question can be closed, such as would you pay?, or open, such as what would you do? A short affirmative continuation is possible too: Imagine the lift stopped — most people would take the stairs.
question word + would / could / should + subject + base form; for a subject question: Who would + base form?
- subject / S —
- The grammatical subject: who or what the clause is about; the verb agrees with it. In The book was written, the book is the subject, although someone else does the action.
- V1 / base form —
- The base verb without to: work, go, be.
Suppose a heatwave closed all schools for a week — who should look after the children?
Suppose a heatwave closed all schools for a week — who should look after the children?
Should asks about responsibility, not a prediction.
Let's say half of our customers left — could we survive?
Let's say half of our customers left — could we survive?
Could emphasises possibility.
Imagine a strike stopped every bus — how would nurses reach the hospital?
Imagine a strike stopped every bus — how would nurses reach the hospital?
An open question with how would.
Suppose two teams proposed rival plans — which one would the board choose, and why?
Suppose two teams proposed rival plans — which one would the board choose, and why?
A two-part question: the choice and the reason.
5. Suppose, Let's say, or Imagine: differences in tone
Suppose is neutral and works in conversation and formal presentations. Supposing is slightly more conversational, while Suppose that marks the clause boundary more clearly and sounds slightly more formal. Let's say is conversational, especially when giving a specific number or example; the shorter Say occurs informally.
Imagine asks listeners to picture a scene, so it often addresses you directly and works well with vivid situations. Imagine (that) + clause is our target pattern, while Imagine + -ing or a noun has a different structure: Imagine living by the sea. That is equally natural but is not a condition containing a subject and finite verb. The opener generally changes the tone rather than the grammar of the condition and question.
Supposing the road were blocked, which route would you take?
Supposing the road were blocked, which route would you take?
Supposing is a more conversational version of Suppose.
Say you have two hours between flights. What would you do with them?
Say you have two hours between flights. What would you do with them?
Say is a short informal form of Let's say.
Imagine that you were the only person who knew the password — how would you feel?
Imagine that you were the only person who knew the password — how would you feel?
Imagine that introduces a complete clause.
Let's say a ticket costs forty pounds and you earn thirty pounds an hour — would you buy it?
Let's say a ticket costs forty pounds and you earn thirty pounds an hour — would you buy it?
The numbers in Let's say help listeners make a calculation.
6. Formulating a useful scenario
A good scenario changes one specific thing: a price, the composition of a group, the number of people, or a deadline. Listeners can then see what to discuss, and the question can be answered. An overly broad condition such as Suppose everything changed provides little direction. Negatives also work in conditions: nobody, no one, none of them.
A comma, dash, or full stop can separate the scenario and question: Suppose we moved the deadline — what would happen? A question helps guide discussion but is not grammatically compulsory. If the consequence or purpose is already clear from context, the scenario can stand alone.
Suppose nobody came to the first lecture — what would the lecturer do?
Suppose nobody came to the first lecture — what would the lecturer do?
Negation in the condition: nobody.
Imagine the museum had no signs at all — how would visitors find their way?
Imagine the museum had no signs at all — how would visitors find their way?
One specific change and one question.
Let's say the project got half the budget. Which tasks would you cut?
Let's say the project got half the budget. Which tasks would you cut?
The condition and question are separated by a full stop.
7. Similar expressions that do not introduce a scenario
Suppose, say, and imagine have other meanings too. I suppose expresses a conjecture about a real fact. Be supposed to describes an obligation or expectation. Let's say inside a sentence can mean approximately, as in at, let's say, six. These uses do not ask anyone to imagine a scenario and do not require a question about consequences.
Boundaries with neighbouring rules: speculative language such as might, probably, and it's likely evaluates the likelihood of a real fact and belongs to a separate rule. Full conditional sentences with if are practised elsewhere. Here we learn to invite someone into a scenario with a brief condition and a shared question.
I suppose she is still at work.
I suppose she is still at work.
A conjecture about a real fact, without a scenario.
You are supposed to wear a helmet on the site.
You are supposed to wear a helmet on the site.
An obligation, not a condition for discussion.
We could meet at, let's say, half past six.
We could meet at, let's say, half past six.
Here let's say suggests a time rather than introducing a scenario.
Imagine living in a lighthouse — what would you do all day?
Imagine living in a lighthouse — what would you do all day?
Imagine + -ing is another natural structure, rather than a finite clause.
Common mistakes
Incorrect:Suppose the council closed the pool, how families would react?
Correct:Suppose the council closed the pool, how would families react?
In a direct question after how, put would before the subject families: how would families react?
Incorrect:Imagine you won a million — what would you did?
Correct:Imagine you won a million — what would you do?
Modal would takes the base form do, not past did.
Incorrect:Suppose we had to cut costs, how we would do it?
Correct:Suppose we had to cut costs, how would we do it?
In a direct question after how, the modal comes before the subject: how would we.
Incorrect:Suppose she have refused the offer last year, what would she have done?
Correct:Suppose she had refused the offer last year, what would she have done?
An alternative past event needs had refused. She have refused also breaks agreement; last year alone is not a universal requirement for the past perfect.
Incorrect:Imagine to live without a phone — what would you miss?
Correct:Imagine living without a phone — what would you miss?
Do not use to + infinitive after imagine: a clause or an -ing form is possible.
Incorrect:Suppose I would be the new manager, what would I change?
Correct:Suppose I were the new manager, what would I change?
In this remote-hypothesis pattern, would is unnecessary in the condition: use the past simple, were or was, and keep would in the question about the consequence.