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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
is unknown only
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "is unknown only" is not correct and does not convey a clear meaning in written English.
It may be intended to express that something is solely unknown, but the phrasing is awkward and unclear. Example: "The reason for the delay is unknown only to the project manager, who has not shared the information with the team."
⚠ May contain grammatical issues
Science
News & Media
Wiki
Alternative expressions(2)
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
He is unknown only in the sense he projects a false, self-protective image to garner the assumed advantages of conformity.
News & Media
However, since the activity ground truth in each ROI is unknown, only the difference in the global calibration factor was considered.
Science
The exact number of half dollars struck by the Confederates with the alternate reverse is unknown; only four of the Confederate coins are known to exist today.
Wiki
While the potential impact of the proposed enhancement is unknown, only 13% of federal drug cases in 2015 involved heroin; the fentanyl penalties would apply in a subset of such cases.
News & Media
As their precise composition and structure is unknown, only core structures of N-glycans were added using GlyProt [53].
Science
For this disease model, we can analytically show that the theoretical genetic maximum of AUC (i.e. when G is known but E is unknown) only depends on the heritability and the average lifetime risk of the disease (See next section) and not on the choice of σG, σE, or α which are difficult to estimate.
Science
Human-verified similar examples from authoritative sources
Similar Expressions
53 human-written examples
Similarly, the filtering method proposed in [61] also addresses parameter uncertainty and time delay, but in this case continuous-time systems are considered and the delay is assumed to be unknown (only the upper bound is available).
As the cause of death was unknown, only all-cause rather than cancer-specific mortality could be assessed.
Science
Infection rates of dogs in Austria are unknown; only 1 case has been reported, and it occurred in a dog imported from the United States (15 ).
Science
If the country of origin was unknown, only those recorded in the central insurance registry before 1 January 2003, when the percentage of immigrants in the country was below 5%, were considered as natives.
Science
Of the three tested enzymes annotated to have methyltransferase activity, CG10903, CG9666 and MT2, whose histone methyltransferase activities are unknown, only CG9666 and MT2 affected histone methylation in S2 cells.
Science
Expert writing Tips
Best practice
For clarity, replace "is unknown only" with phrases like "is known to very few" or "is only known by a few" to emphasize the limited scope of knowledge.
Common error
Avoid using "is unknown only" as it can sound awkward. Instead, use more direct phrasing, such as "is only known by a few" for better clarity.
Source & Trust
79%
Authority and reliability
2.8/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "is unknown only" functions as a descriptor, attempting to specify the extent to which something is not known. However, as Ludwig AI points out, the phrasing is awkward and not grammatically ideal.
Frequent in
Science
66%
News & Media
16%
Wiki
16%
Less common in
Formal & Business
0%
Encyclopedias
0%
Social Media
0%
Ludwig's WRAP-UP
In summary, the phrase "is unknown only" is used to express that something is not widely known, but its phrasing is considered awkward and grammatically incorrect by Ludwig AI. While it appears in a variety of sources including science, news and media, and wiki, clearer and more common alternatives such as "is solely unknown" or "is only known by a few" are recommended for better clarity and precision. The phrase's function is descriptive, aiming to qualify the state of being unknown, but its effectiveness is limited by its non-standard construction.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
is only known by a few
Indicates that the knowledge is limited to a small number of individuals.
is solely unknown
Emphasizes that the information is exclusively unknown, highlighting the single aspect of being unknown.
is exclusively unknown
Emphasizes that something is only not known, and nothing else is known about it.
is known to very few
Indicates that the information is not widely known, implying a limited audience with knowledge of it.
is uniquely unknown
Suggests the aspect of being unknown is distinct and unparalleled.
is privy to few individuals
Suggests that the knowledge is restricted to a select group of people, implying exclusivity.
is not widely recognized
Highlights the lack of general awareness about the subject, focusing on the breadth of unknowing.
remains obscure to most
Emphasizes the hidden or unclear nature of the information for the majority of people.
is not common knowledge
States that the information is not generally known or understood.
is limited in awareness
Highlights that the understanding or knowledge of the subject is restricted.
FAQs
How can I rephrase "is unknown only" for better clarity?
Consider using alternatives such as "is solely unknown", "is known to very few", or "is only known by a few" depending on the context.
What does "is unknown only" imply?
The phrase suggests that knowledge about something is restricted to a small group or is not widely recognized, but it's phrased awkwardly.
Is "is unknown only" grammatically correct?
While understandable, "is unknown only" is not the most grammatically sound phrasing. More common and clearer alternatives exist, such as "is solely unknown".
When is it appropriate to use "is unknown only"?
It's generally better to avoid "is unknown only" in favor of more precise and common phrases like "is only known by a few" or "is not widely recognized" for better communication.
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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
79%
Authority and reliability
2.8/5
Expert rating
Real-world application tested