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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
an issue of which
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "an issue of which" is correct and usable in written English.
It can be used when referring to a specific issue that has been previously mentioned or is known in the context of the discussion. Example: "The report highlighted an issue of which the committee was already aware."
✓ Grammatically correct
News & Media
Science
Encyclopedias
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
13 human-written examples
It's not so much an issue of which hat to wear, but whether to wear any hat at all.
News & Media
From a career point of view, it was tricky timing, an issue of which Parker was well aware.
News & Media
He wrote books on science and international affairs and produced a number of articles on eugenics, an issue of which he was a strong supporter.
Encyclopedias
So what is he playing at?The answer is that Europe is an issue of which Mr Cameron has little grasp and may be about to lose control.
News & Media
After watching the events of this weekend, I'm quite sure I was wrong: Snowden has indeed altered U.S.-China relations, by giving China new strength on an issue of which it was struggling to gain any leverage at all.
News & Media
But Saadi's legal representative, Nick Kaufman, a lawyer based in Jerusalem, told the Bureau of Investigative Journalism: "This is an issue of which my client and I are fully aware.
News & Media
Human-verified similar examples from authoritative sources
Similar Expressions
47 human-written examples
But the minimum wage is an example of an issue on which he has held constant.
News & Media
That is why this is an issue on which many politicians of all stripes agree.
News & Media
"There is an issue of manslaughter, which is reckless killing," Mr. Rubenstein said.
News & Media
The Co-op will pay just £350m initially through an issue of bonds which will be underwritten by Lloyds in a highly unusual move.
News & Media
This simultaneity raises an issue of endogeneity, which unless accounted for, will lead to biased results.
Science
Expert writing Tips
Best practice
Use "an issue of which" in formal writing when you want to specifically refer back to an issue that has already been clearly identified and needs further clarification or detail. It's most effective when introducing a subordinate clause that expands on the initial issue.
Common error
Avoid using "an issue of which" in informal contexts or everyday conversation, as it can sound overly formal and stilted. In more casual settings, simpler alternatives like "an issue that" or "an issue about" are generally more appropriate.
Source & Trust
84%
Authority and reliability
4.3/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "an issue of which" functions as a prepositional phrase, often introducing a relative clause that elaborates on a previously mentioned issue. Ludwig indicates that this phrase is grammatically sound and usable in formal contexts.
Frequent in
News & Media
60%
Science
30%
Encyclopedias
10%
Less common in
Formal & Business
0%
Wiki
0%
Reference
0%
Ludwig's WRAP-UP
In summary, the phrase "an issue of which" is a grammatically correct prepositional phrase used to introduce further details about a previously mentioned issue. While Ludwig identifies it as grammatically sound, its usage is relatively uncommon and more appropriate in formal writing, scientific contexts, news reporting, and encyclopedic entries. When writing, be mindful of the potential for a more casual rephrasing. Some alternatives are "a matter of which", or "an issue that", depending on context.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
a matter of which
Replaces "issue" with "matter", softening the tone while retaining the core meaning of a problem or topic.
a topic of which
Substitutes "issue" with "topic", shifting the focus towards a subject of discussion rather than a problem.
an aspect of which
Changes "issue" to "aspect", highlighting a specific facet or part of a broader subject.
a concern of which
Replaces "issue" with "concern", emphasizing worry or interest in a particular matter.
a problem of which
Directly uses "problem" instead of "issue", making the negative connotation more explicit.
a question of which
Changes "issue" to "question", framing it as something to be investigated or debated.
an element of which
Substitutes "issue" with "element", focusing on a constituent part or component.
a facet of which
Similar to "aspect", but perhaps implying a slightly more complex or multi-sided view.
a challenge of which
Replaces "issue" with "challenge", highlighting the difficulty or obstacle involved.
an area of which
Substitutes "issue" with "area", focusing on a specific domain or field.
FAQs
How can I use "an issue of which" in a sentence?
Use "an issue of which" to introduce a clause that provides additional information about a previously mentioned problem or topic. For example: "Climate change is an issue of which many people are aware, but few fully understand the potential consequences."
What are some alternatives to "an issue of which"?
Alternatives include "a matter of which", "a topic of which", or "an issue that". The best choice depends on the specific context and desired level of formality.
Is it always necessary to use "of which" after "an issue"?
No, it's not always necessary. You can often rephrase the sentence for clarity and conciseness. For example, instead of "This is an issue of which I am well aware", you can say "I am well aware of this issue".
What is the difference between "an issue of which" and "an issue that"?
"An issue of which" is generally more formal and is used to introduce a relative clause that provides additional information. "An issue that" is less formal and more commonly used in general writing and speech.
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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
84%
Authority and reliability
4.3/5
Expert rating
Real-world application tested