Speculation instead of a categorical statement
When we observe a fact, such as a fall in numbers or a rise in scores, but do not know why it happened, academic writing distinguishes what was observed from what is only hypothesised. State the observation directly and place the proposed cause in a frame that signals a hypothesis.
English academic style uses established frames and modal verbs to express possibility, conceivable explanations and what evidence may indicate. Conversational maybe or I guess sounds too informal for the academic register practised here.
The sea temperature rose, and the cod disappeared from the bay.
The sea temperature rose, and the cod disappeared from the bay.
These are two observations; a connection between them is not asserted.
It is possible that warmer water drove the cod out of the bay.
It is possible that warmer water drove the cod out of the bay.
The cause is placed inside a possibility frame, making it a hypothesis.
Warmer water drove the cod out of the bay.
Warmer water drove the cod out of the bay.
Without the frame, the same cause is presented as established.
The frame it is possible / conceivable / plausible that…
Follow It is possible / conceivable / plausible with a full clause, usually introduced by that: It is possible that the bridge will close. In some contexts, that can be omitted: It’s possible the bridge will close. Do not insert the bridge to close here without a finite verb.
Do not confuse this with it is possible to + verb, which concerns the possibility of performing an action rather than speculation. Conceivable sounds more formal and often suggests a remote but imaginable possibility; plausible suggests a credible one. A related, more conversational frame is it could be that.
It is + possible / conceivable / plausible + (that) + subject + finite verb
- 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.
- verb / V —
- A word for an action or state, such as work or be. The pattern determines its form.
It is conceivable that the tomatoes failed because the greenhouse stayed too cold at night.
It is conceivable that the tomatoes failed because the greenhouse stayed too cold at night.
The clause has its own subject and past-tense predicate.
It is plausible that the choir's growth is linked to the new rehearsal room.
It is plausible that the choir's growth is linked to the new rehearsal room.
The clause’s predicate is a passive form with is.
It could be that the printer jammed because of the humid air.
It could be that the printer jammed because of the humid air.
It could be that is a more conversational frame conveying the same meaning.
It is possible to book the room online.
It is possible to book the room online.
Possible to concerns the possibility of an action here, not speculation.
Explanatory frames: one explanation could be that…
To list several hypotheses, useful frames include one (possible) explanation is/could be that…, another possibility is that…, and a possible reason for X is that…. Be is followed by that and a full clause. Because is often heard after be in conversation, but that is the standard choice in formal writing here.
These frames help structure a paragraph: first a fact, then a first explanation, then another possibility, and finally a way to test them. There is a possibility that… also introduces speculation, although it is slightly more cumbersome.
One (possible) explanation is / could be + that + subject + predicate
- 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.
One explanation could be that commuters now work from home on Fridays.
One explanation could be that commuters now work from home on Fridays.
The modal could also softens the frame itself.
A possible reason for the shortfall is that the grant arrived late.
A possible reason for the shortfall is that the grant arrived late.
This frame uses the noun reason; even with is and no modal, possible already marks the explanation as tentative.
Another possibility is that the survey reached only younger residents.
Another possibility is that the survey reached only younger residents.
Another requires a first explanation to have been mentioned already.
There is a possibility that the ferry will be cancelled.
There is a possibility that the ferry will be cancelled.
This is another frame with that and a future form in the clause.
Modals and evidence: this might indicate that…
When interpreting data, a result or figure becomes the subject, and an evidential verb such as indicate, suggest or imply follows may, might or could. A modal requires the base form: it might suggest, not it might suggests or it might to suggest.
May often sounds slightly more formal than might, and could is also common in this function. There is no sharp difference in strength between them in this context. Prove, by contrast, is not a hedge: it declares the conclusion established.
Result / this + may / might / could + indicate / suggest / imply + that + subject + predicate
- 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.
The drop in complaints might suggest that the new help desk is working.
The drop in complaints might suggest that the new help desk is working.
Modal + evidential verb + that-clause.
These readings could imply that the river is carrying more silt than before.
These readings could imply that the river is carrying more silt than before.
The subject is the data, not a person.
A rise in repeat visits may indicate that visitors value the new exhibition.
A rise in repeat visits may indicate that visitors value the new exhibition.
May contributes a more formal tone.
Tense inside the that-clause
The frame shows the time of the assessment, while the subordinate clause shows the time of the event. It is possible that the village was abandoned is a present hypothesis about the past. It was possible that the village had already been abandoned presents a possibility from a past reference point. A present-tense frame is not compulsory.
There is also a separate past modal form for speculation: may/might have + V3, as in frost may have damaged the pipe. That belongs to another topic on past modal forms; here, the focus is on frames whose clause shows the event’s tense directly.
It is conceivable that the village was abandoned after a series of poor harvests.
It is conceivable that the village was abandoned after a series of poor harvests.
The subordinate clause is in the past, while the frame is in the present.
It is possible that the lake is shrinking faster than the report states.
It is possible that the lake is shrinking faster than the report states.
An ongoing present process uses the Present Continuous.
It is possible that the shop will close next year.
It is possible that the shop will close next year.
Will expresses future time.
Frost may have damaged the pipe.
Frost may have damaged the pipe.
This past modal form belongs to a related topic and is included only for comparison.
How much caution is needed?
The strength of a claim should match its basis. A directly established result can often be stated without additional softening; a limited or uncertain conclusion is better marked with possibility language. The purpose of the communication also matters, so cautious wording for confirmed data is not prohibited.
Do not pile up markers unnecessarily: might possibly perhaps usually burdens a statement. Might possibly itself is possible if it emphasises a small possibility. It is likely that and may well often express a stronger expectation, but no form fixes a percentage.
The audit confirms that two of the five invoices were paid twice.
The audit confirms that two of the five invoices were paid twice.
The fact is confirmed, so a hedge is unnecessary.
It is conceivable that the other invoices were paid twice as well, but the audit does not show this.
It is conceivable that the other invoices were paid twice as well, but the audit does not show this.
This is speculation about something the evidence does not confirm.
It is possible that the delay was caused by staff shortages.
It is possible that the delay was caused by staff shortages.
One hedge is enough.
Scope: what is not practised here
This lesson covers speculation about what is, was or will be the case. Conditional patterns such as if + Past Simple, would + base form, and invitations with suppose or imagine are covered in related lessons.
Strong deductions, such as they must be out and he can’t have left, are also a separate topic: these are conclusions from strong evidence rather than cautious speculation about a possible cause.
If the council raised parking fees, the shop might close.
If the council raised parking fees, the shop might close.
This is a conditional sentence, covered by a separate related rule.
Suppose the council raised parking fees; what would happen to the shop?
Suppose the council raised parking fees; what would happen to the shop?
An imagined scenario for discussion is a different topic.
They said they were leaving for the airport at six, so they must be out by now.
They said they were leaving for the airport at six, so they must be out by now.
Must presents a strong deduction from a known plan; it is the speaker’s assessment, not a guarantee that the plan was carried out.
Common mistakes
Incorrect:This might indicates that the sensor was faulty.
Correct:This might indicate that the sensor was faulty.
The modal might is followed by the base form without -s: might indicate.
Incorrect:It is possible that the fall linked to the new tax.
Correct:It is possible that the fall is linked to the new tax.
The clause after that needs a complete predicate: the passive requires a form of be.
Incorrect:It is possible that rents to rise next spring.
Correct:It is possible that rents will rise next spring.
That is followed by a full clause with a finite verb, not a to-infinitive.
Incorrect:One explanation could be that the demand rises last year.
Correct:One explanation could be that the demand rose last year.
The clause’s tense must match the event’s time: last year requires a past tense.
Incorrect:This could to suggest that the policy has failed.
Correct:This could suggest that the policy has failed.
Do not put to after could: a modal takes the base form.