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Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.

Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
could have supposed
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "could have supposed" is correct and usable in written English.
It can be used to express a hypothetical situation in the past where one might have had a belief or assumption. Example: "Given the evidence presented, I could have supposed that the outcome would be different."
✓ Grammatically correct
News & Media
Academia
Science
Alternative expressions(16)
might have thought
could have believed
might have assumed
might have believed
could have guessed
could have imagined
could have expected
could have envisioned
might have conceived
could have anticipated
could have foreseen
could have speculated
could have waited
could have thought
could have caused
could have chosen
Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Human-verified examples from authoritative sources
Exact Expressions
7 human-written examples
My guess is that nobody at the time could have supposed that arguments about the foundations of mathematics would ever have a practical outcome.
News & Media
Later he would say more harshly that Charley had inherited from his mother "an indescribable lassitude of character" and that "I think he has less fixed purpose and energy than I could have supposed possible in my son".
News & Media
Thus it should be no surprise that the self-styled democratic socialist Bernie Sanders is challenging Hillary Clinton for the Democratic presidential nomination more effectively than even he could have supposed 12 months ago.
News & Media
No Congressman could have supposed that, in passing an amendment to that section proposed by the Postmaster General and recommended by the committees dealing with the postal service, he was creating a new crime with respect to government property generally". Id., at 957, n. 3a.
Academia
Karbo does learn a number of poignant things that children of the dying must come to accept: that cancer is a relentless sneak of a disease, that quotidian trouble doesn't quit for a crisis, that the heart doesn't break clean, that people hang onto life longer than you could have supposed and are gone from you long before they die.
News & Media
I could have supposed all these things, like, 'Oh, it'll be really educational,' but we didn't know.
News & Media
Human-verified similar examples from authoritative sources
Similar Expressions
53 human-written examples
Duncan later wrote that, "To be deserted by my own fleet in the face of the enemy is a disgrace which I believe never before happened to a British admiral, nor could I have supposed it possible".
Wiki
Could they really have supposed there would be no spillage from their hyperbole?
News & Media
In conclusion, no major alterations have been found in DGC, ECM or sarcolemma integrity in AQP4−/− mice as could have been supposed to occur.
Science
You could have, I suppose, done this movie in Canada, but it wouldn't have been the same type of story.
News & Media
And it refused to allow a recount to proceed under uniform standards that could have corrected the supposed problem.
News & Media
Expert writing Tips
Best practice
When using "could have supposed", ensure the context clearly indicates that the supposition was made in the past and is now known to be inaccurate.
Common error
Avoid using "could have supposed" to describe current beliefs or assumptions. This phrase strictly refers to a past supposition that is no longer valid.
Source & Trust
87%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "could have supposed" functions as a modal verb phrase expressing a hypothetical past belief or assumption that was likely incorrect or disproven. As Ludwig AI explains, it's used to reflect on something that one might have previously thought to be true.
Frequent in
News & Media
58%
Academia
25%
Science
17%
Less common in
Formal & Business
0%
Encyclopedias
0%
Wiki
0%
Ludwig's WRAP-UP
In summary, "could have supposed" is a grammatically sound phrase used to express a past assumption or belief that turned out to be incorrect. As Ludwig AI confirms, the phrase is correct and usable in written English. While not exceedingly common, it appears in a variety of reputable sources, including news media and academic publications. When writing with this phrase, remember that it strictly refers to past suppositions. Consider alternatives like "might have assumed" or "might have believed" for nuanced variations in meaning. Be mindful of tense consistency to prevent misuse. Ultimately, understanding the contexts in which this phrase appears helps writers deploy it effectively to add depth and reflection to their work.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
might have assumed
Replaces "supposed" with "assumed", implying a slightly stronger degree of confidence in the past belief.
might have believed
Substitutes "supposed" with "believed", suggesting a more firm conviction in the past.
could have imagined
Replaces "supposed" with "imagined", emphasizing the speculative nature of the past thought.
could have expected
Substitutes "supposed" with "expected", indicating an anticipation based on prior knowledge or experience.
might have presumed
Replaces "supposed" with "presumed", suggesting a belief taken for granted without concrete evidence.
might have thought
Uses "thought" in place of "supposed", offering a more general and less formal alternative.
could have envisioned
Substitutes "envisioned" for "supposed", highlighting the mental picture or concept one might have formed.
might have conceived
Replaces "supposed" with "conceived", implying a more elaborate and thoughtful formation of the belief.
could have anticipated
Substitutes "anticipated" for "supposed", focusing on expecting something to happen.
might have gathered
Replaces "supposed" with "gathered", suggesting an inference based on available information.
FAQs
How can I use "could have supposed" in a sentence?
You can use "could have supposed" to express a past assumption that turned out to be incorrect, for example: "I /s/could+have+supposed that the meeting would be productive, but it was a complete waste of time."
What's a more formal alternative to "could have supposed"?
For a more formal tone, consider using "might have assumed" or "might have believed". These alternatives convey a similar meaning with a slightly elevated level of formality.
Is it correct to use "could have supposed" for current assumptions?
No, "could have supposed" refers to a past assumption. For current assumptions, use phrases like "I suppose" or "I assume".
What is the difference between "could have guessed" and "could have supposed"?
"Could have guessed" implies a less formal, more intuitive estimation, while "could have supposed" suggests a more considered, though ultimately incorrect, assumption.
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Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Source & Trust
87%
Authority and reliability
4.5/5
Expert rating
Real-world application tested