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Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
an well known
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "an well known" is not correct in written English.
It should be "a well known" because "well" begins with a consonant sound. Example: "He is a well known author in the literary community."
⚠ May contain grammatical issues
Science
News & Media
Wiki
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
2-Chlorocarbinol (CC-2) is a potential decontaminant of sulfur mustard (SM), an well known warfare agent.
Human-verified similar examples from authoritative sources
Similar Expressions
59 human-written examples
Consider a variant of a well known example.
Science
Variability of thermo-mechanical properties within a composite part is a well known issue.
The second is a well known model of a Boeing 767 aircraft at a flutter condition.
Science
Use a well known dealer over a less well known one.
Wiki
We propose a GP algorithm linked with Matlab/Simulink, a well known tool amongst control engineers.
Science
PQ is an herbicide widely used in agriculture and a well known ROS-generating chemical.
Science
It is a well known fact that it is a NP-hard problem [11].
Simulation (a pre-order) over Kripke structures is a well known formal verification technique.
A weighted least squares curves fitting method, based on a well known conformal mapping, is described.
It is a well known method to approximate the derivatives of a variable with small variations.
Expert writing Tips
Best practice
Always use the article "a" before "well known" because "well" begins with a consonant sound. For example, use "a well-known author" instead of "an well known author".
Common error
Avoid using "an" before adjectives that start with a consonant sound. The correct usage depends on the sound, not the letter, of the following word. If the word starts with a vowel sound, use "an"; otherwise, use "a".
Source & Trust
83%
Authority and reliability
1.8/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "an well known" attempts to function as a modifier, specifically an adjective phrase, to describe something as recognized or familiar. However, Ludwig AI indicates this phrasing is grammatically incorrect due to the misuse of the article "an" before a word beginning with a consonant sound.
Frequent in
Science
50%
News & Media
25%
Wiki
25%
Less common in
Formal & Business
0%
Reference
0%
Encyclopedias
0%
Ludwig's WRAP-UP
In summary, the phrase "an well known" is grammatically incorrect because the article "an" should only be used before words that begin with a vowel sound. The correct form is "a well known". As Ludwig AI suggests, avoid using "an" before words starting with consonant sounds. While the phrase does appear in some sources, it's important to use the grammatically correct alternative for clarity and professionalism. The phrase is rare, and you should prefer alternatives like "widely recognized" or "commonly acknowledged".
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
a well-known
Corrects the article to "a" for proper grammar with a consonant-starting adjective.
widely recognized
Replaces "well known" with a synonym emphasizing broad acknowledgement.
generally accepted
Implies that something is commonly agreed upon or understood.
commonly acknowledged
Highlights the fact that something is openly admitted or recognized.
established
Focuses on the long-term recognition and acceptance of something.
renowned
Suggests a high level of fame and respect.
famous
Indicates widespread knowledge and recognition.
notable
Emphasizes the importance and worthiness of attention.
prominent
Highlights the visibility and importance of something.
celebrated
Indicates that something is widely praised and admired.
FAQs
What's the correct way to say "well known"?
The correct phrase is "a well known". The article "a" is used because the adjective "well" begins with a consonant sound.
Is "an well known" grammatically correct?
No, "an well known" is grammatically incorrect. The article "an" is used before words that begin with a vowel sound, while "a" is used before words that begin with a consonant sound.
What are some alternatives to "a well known"?
You can use alternatives like "widely recognized", "commonly acknowledged", or "established" depending on the context.
How can I remember when to use "a" versus "an"?
Remember that "a" is used before words starting with a consonant sound, and "an" is used before words starting with a vowel sound. For example, "a well" versus "an apple".
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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
83%
Authority and reliability
1.8/5
Expert rating
Real-world application tested