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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
a key reason for
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "a key reason for" is correct and usable in written English.
It can be used to indicate an important factor or explanation for a particular situation or outcome. Example: "A key reason for the project's success was the team's dedication and hard work."
✓ Grammatically correct
News & Media
Science
Formal & Business
Alternative expressions(17)
a major factor in
a significant cause of
a primary cause of
the main reason for
a crucial factor in
the principal cause of
a predominant factor in
a key consideration for
a fundamental reason for
a key justification for
a key rationale for
a substantial reason for
a key basis for
a pivotal reason for
a core reason for
a prime reason for
a primary reason for
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
58 human-written examples
Mr. Scott missed a key reason for audiences' current appetite for fantasy movies.
News & Media
A key reason for this Sunday afternoon drama was Bjorn's latest collapse.
News & Media
Support among the young appears to be a key reason for the BJP's success.
News & Media
A key reason for Fisher's involvement in Corbyn's Labour party is the anti-austerity stance.
News & Media
Balkam points to the anonymity allowed on Kik as a key reason for his concern.
News & Media
The report notes that a key reason for this is how demanding the job can be.
News & Media
Lack of supply has been cited as a key reason for rising prices across the country.
News & Media
A key reason for the buying power is a still strong employment market.
News & Media
The group cited Israel's construction surge as a key reason for the failure.
News & Media
A key reason for this unpopularity is the widespread perception that the strikes overwhelmingly kill civilians.
News & Media
But in the early 1940's ideology was a key reason for espionage, both in the United States and Britain.
News & Media
Expert writing Tips
Best practice
When using "a key reason for", ensure that the reason you are citing is genuinely significant and not merely a contributing factor of lesser importance. Provide evidence or context to support your claim.
Common error
Avoid using "a key reason for" when the factor you're describing is only a minor contributor. Overstating its importance can weaken your argument and mislead the reader.
Source & Trust
86%
Authority and reliability
4.6/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "a key reason for" functions as a causal connector, introducing a significant cause or explanation for a particular event or situation. As Ludwig AI confirms, this phrase is widely accepted and used.
Frequent in
News & Media
49%
Science
32%
Formal & Business
8%
Less common in
Wiki
5%
Encyclopedias
3%
Reference
3%
Ludwig's WRAP-UP
In summary, "a key reason for" is a versatile phrase used to introduce a significant cause or explanation. Ludwig AI confirms its grammatical correctness and wide acceptance. It's most commonly found in news articles and scientific publications. When using this phrase, ensure that the reason you're citing is indeed a primary factor and provide adequate support. Remember to avoid overstating the importance of minor contributors. Alternative phrases include "a primary cause of" and "a major factor in". By following these guidelines, you can effectively use "a key reason for" in your writing.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
a primary cause of
Focuses more directly on causation rather than explanation.
a major factor in
Emphasizes the significance of the factor contributing to an outcome.
the main reason for
Highlights the principal reason among others.
an important factor for
Similar in meaning, but puts slightly less emphasis on the reason being the most important.
a significant cause of
Focuses on the importance of the cause.
a crucial factor in
Highlights the factor as critical or essential.
the principal cause of
Points out the leading cause.
a central explanation for
Emphasizes the explanatory aspect of the reason.
a foremost cause of
Emphasizes the prominence of the cause.
a predominant factor in
Highlights the prevalence or dominance of the factor.
FAQs
What does "a key reason for" mean?
The phrase "a key reason for" indicates a primary or significant cause or explanation for a particular situation or event.
What can I say instead of "a key reason for"?
You can use alternatives like "a primary cause of", "a major factor in", or "the main reason for" depending on the context.
Is it correct to say "the key reason for" instead of "a key reason for"?
Yes, both are grammatically correct. "The key reason for" suggests there is one primary reason, while "a key reason for" suggests it is one of several important reasons.
How do I use "a key reason for" in a sentence?
You can use "a key reason for" to introduce an explanation or cause. For example, "A key reason for the company's success was its innovative marketing strategy."
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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
86%
Authority and reliability
4.6/5
Expert rating
Real-world application tested