Used and loved by millions
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
a common instance
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "a common instance" is correct and usable in written English.
It can be used to refer to a frequently occurring example or situation in a particular context. Example: "In many urban areas, a common instance of traffic congestion occurs during rush hour."
✓ Grammatically correct
Science
News & Media
Alternative expressions(19)
a typical example
a frequent occurrence
a usual case
a common example
a typical case
a usual occurrence
a regular event
a widespread phenomenon
a typical scenario
a routine matter
a familiar sight
a general pattern
a common circumstance
a common stage
a common situation
a common case
a common scenario
a common fact
a typical instance
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
2 human-written examples
Each "OUTi" is checked to find out a common instance present in all outlier arrays.
Science
A common instance where people assume they're covered, but they're not, is if there's a large or total loss of their home and new building codes drives up the cost of building a replacement.
News & Media
Human-verified similar examples from authoritative sources
Similar Expressions
58 human-written examples
A famous example of a pair of formulas that have no common instance is A → A and A → A → B.
Science
That might have been the end of Charles' story, a far too common instance of NYPD harassing people of color in high crime neighborhoods, were it not for a class action lawsuit filed by the New York Civil Liberties Union claiming the New York Police Department had acted with "deliberate indifference" to scores of wrongful arrest complaints by residents and guests of Clean Halls building.
News & Media
She noted that there was one other common instance in which an American's name would be included: "If it's evidence of a crime".
News & Media
The key to the applicability of detachment is to find a common substitution instance of the minor premise and of the antecedent of the major premise.
Science
These are of course statistically principled, but in practice the metric can explode at the extremes: the most common instance is for binomial data with 0% or 100% accuracy (i.e., the extremes of a nice psychometric function).
Science
10 25–27 The Beers criteria have also been criticised for not being sufficiently inclusive of a number of common instances of PIP. 6 15 In particular, Beers only lists drugs to avoid, but does not include other categories of PIP, such as drug drug and drug disease interactions, drug duplications or underuse and overuse of medications.
Science
26 29 They have also been criticised for not being sufficiently inclusive of a number of common instances of PIP. 8 17 In particular, Beers only lists drugs to avoid, but does not include other categories of PIP, such as drug drug and drug disease interactions, drug duplications or underuse and overuse of medications.
Science
Clean air is a commons, an instance of market failure, dependent on government protection for its existence; farming is part of a market.
News & Media
Each line represents the percentage of common instances for a given pair of strategies (dc-c, dc-ff, c-ff).
Expert writing Tips
Best practice
Use "a common instance" when you want to refer to an event, situation or example that occurs frequently or is widely recognized. It adds a layer of formality to your writing.
Common error
While "a common instance" is correct, consider whether a simpler phrase like "a typical example" would be more appropriate. Overusing formal language can make your writing sound stilted.
Source & Trust
87%
Authority and reliability
4.3/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "a common instance" functions as a noun phrase, often serving as a subject complement or an appositive. Ludwig examples showcase its use to introduce familiar or recurring situations. This follows standard English grammar.
Frequent in
Science
50%
News & Media
50%
Formal & Business
0%
Less common in
Encyclopedias
0%
Wiki
0%
Reference
0%
Ludwig's WRAP-UP
In summary, "a common instance" is a grammatically sound noun phrase used to introduce a typical or frequent occurrence. Ludwig indicates that the phrase is relatively formal, suitable for scientific writing, news reports, or formal business communication. While correct, writers should consider whether a simpler alternative such as "a typical example" or "a frequent occurrence" might be more appropriate depending on the context.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
a typical case
Replaces "instance" with "case", emphasizing a specific occurrence that is representative of others.
a frequent example
Substitutes "common" with "frequent" and "instance" with "example", highlighting the regularity of the occurrence.
a usual occurrence
Replaces "common instance" with "usual occurrence", focusing on the habitual nature of the event.
a regular event
Changes "common instance" to "regular event", indicating a predictable and recurring incident.
a prevalent situation
Replaces "common instance" with "prevalent situation", emphasizing the widespread nature of the scenario.
a widespread phenomenon
Changes the phrase to highlight a phenomenon that is broadly observed.
a typical scenario
Focuses on a scenario that is representative and often encountered.
a routine matter
Indicates something that is handled as part of a normal procedure.
a familiar sight
Highlights something that is frequently seen or experienced.
a general pattern
Refers to a recognized and repeated sequence or form.
FAQs
How can I use "a common instance" in a sentence?
You can use "a common instance" to introduce a typical or frequent example. For example: "A common instance of traffic congestion is during rush hour."
What are some alternatives to "a common instance"?
Some alternatives include "a typical example", "a frequent occurrence", or "a usual case" depending on the specific context.
Is "a common instance" formal or informal?
"A common instance" is generally considered more formal. In more casual contexts, you might prefer "a typical example" or "a usual situation".
What's the difference between "a common instance" and "a common example"?
While both phrases are similar, "a common instance" often refers to a specific occurrence or situation, whereas "a common example" usually refers to a general illustration or model.
Editing plus AI, all in one place.
Stop switching between tools. Your AI writing partner for everything—polishing proposals, crafting emails, finding the right tone.
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
4.3/5
Expert rating
Real-world application tested