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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
be unable to fathom
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "be unable to fathom" is correct and usable in written English.
It can be used when expressing a lack of understanding or comprehension of something complex or difficult to grasp. Example: "After hearing the news, I was unable to fathom how such a tragedy could occur."
✓ Grammatically correct
News & Media
Wiki
Alternative expressions(3)
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
1 human-written examples
It was demoralizing to discover that in spite of my record-keeping--a feat of human organization and skill unmatched by anyone whose uncle was not Ivan Ferderbar, I would be unable to fathom the instructions for filing my taxes.
News & Media
Human-verified similar examples from authoritative sources
Similar Expressions
59 human-written examples
UNTIL he began considering what it meant to represent America in Venice, he was unable to fathom how to turn his rage into metaphor.
News & Media
But for reasons I was unable to fathom at the time, I clung to a conviction that I must do as she told me.
News & Media
Starring Josh Brolin as a man locked away for 20 years (up from 15 in the original) in a hotel-like prison by an unseen nemesis for reasons he is unable to fathom, Lee's version is said to be based more directly on the 1996 Japanese manga that spawned Park's mystery thriller.
News & Media
James, needing to make himself taller for some reason, draws himself up, and then asks, "You are saying you work, live, and sleep here, and for food you collect the leftovers from my restaurant?" Ahmed looks offended, but James is unable to fathom why.
News & Media
Unlike Locke, the narrator of the poem knows that he is unable to fathom the universe, but still questions the matter.
Wiki
As live-for-the-moment eighth graders, Ellen and I were unable to fathom that life could one day turn fragile.
News & Media
Watching a detainee make a frustrated weekly call home to his family, who are unable to fathom the fact that the Australian government has locked them up indefinitely a wife who believes her husband must be lying to her and living it up in Sydney, because the situation he describes simply cannot be possible.
News & Media
They are terrified of failure, particularly their own and of being unable to fathom the consequences when things go wrong.
Wiki
Oliver White, economist at Fathom, says many African countries will be unable to balance their budgets without spending cuts following what is likely to be a huge fall in oil – and mining-related tax revenues.
News & Media
Major Kusanagi, the big-bosomed bionic heroine of Mamoru Oshii's mesmerising Ghost in the Shell (one of the inspirations for The Matrix and a plot I'm still unable to fathom, even after repeated viewings) is frequently nude or leaping around in a form-fitting bodysuit that makes her look naked.
News & Media
Expert writing Tips
Best practice
Use "be unable to fathom" to express a strong sense of bewilderment or incomprehension, particularly when facing complex or abstract ideas. For simpler situations, consider using "not understand".
Common error
Avoid using "be unable to fathom" when referring to literal depths or measurements, as "fathom" also relates to a unit of depth. Instead, use a different verb to describe measuring depth, such as "measure" or "determine".
Source & Trust
85%
Authority and reliability
4.1/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "be unable to fathom" functions as a verb phrase expressing a lack of comprehension or understanding. Ludwig AI confirms its grammatical correctness. It indicates an inability to deeply understand something complex or obscure.
Frequent in
News & Media
75%
Wiki
15%
Formal & Business
10%
Less common in
Science
0%
Encyclopedias
0%
Reference
0%
Ludwig's WRAP-UP
The phrase "be unable to fathom" is a grammatically sound way to express a lack of understanding, particularly when dealing with complex or abstract subjects. As noted by Ludwig, the phrase is correct and usable in written English. While not the most frequent expression, it effectively conveys bewilderment or incomprehension. Consider simpler alternatives like "not understand" in less formal contexts. Ludwig's examples demonstrate its use in news, wiki and formal writing, solidifying its place as a versatile tool for expressing cognitive limitations. Usage guidance suggests avoiding it in literal depth contexts due to the word "fathom" also representing a unit of measurement.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
cannot comprehend
Focuses on the inability to grasp the meaning.
cannot understand
Emphasizes a general lack of understanding.
fail to grasp
Highlights the failure to seize or understand something.
struggle to comprehend
Indicates a difficulty in understanding.
find it hard to understand
Shows difficulty in the process of understanding.
be at a loss to understand
Implies confusion and a lack of understanding.
be incapable of understanding
Highlights a complete lack of capacity to understand.
be beyond one's comprehension
Indicates that something is too complex to understand.
be unable to make sense of
Focuses on the inability to find meaning or coherence.
be unable to decipher
Highlights the inability to interpret or decode something.
FAQs
What does "be unable to fathom" mean?
The phrase "be unable to fathom" means to be incapable of understanding something, often because it is too complex or mysterious. It suggests a deep level of incomprehension.
How can I use "be unable to fathom" in a sentence?
You can use "be unable to fathom" to express your lack of understanding. For example, "I "am unable to fathom" why they made that decision."
What can I say instead of "be unable to fathom"?
Alternatives include phrases like "cannot comprehend", "cannot understand", or "fail to grasp", depending on the specific context.
Is "be unable to fathom" formal or informal?
"Be unable to fathom" is generally considered a neutral to slightly formal phrase. While appropriate in many contexts, simpler alternatives may be preferable in very informal settings.
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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
85%
Authority and reliability
4.1/5
Expert rating
Real-world application tested