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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
key reason for
Grammar usage guide and real-world examplesUSAGE SUMMARY
'key reason for' is a correct and usable phrase in written English.
This phrase is usually used to introduce the explanation or explanation of a particular situation or condition. For example: "The key reason for the drop in sales this month is the lack of promotional campaigns."
✓ Grammatically correct
News & Media
Science
Formal & Business
Encyclopedias
Wiki
Reference
Alternative expressions(17)
primary cause of
the most important factor
chief factor in
principal motive behind
underlying basis for
driving force behind
fundamental aspect of
core element of
pivotal reason for
fundamental reason for
essential reason for
key basis for
core reason for
substantial reason for
primary reason for
key necessity for
crucial 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
That touches on another key reason for the UFC's success.
News & Media
Mr. Scott missed a key reason for audiences' current appetite for fantasy movies.
News & Media
The key reason for saving in the home is reliable access.
News & Media
Support amongst the young appears to be one key reason for the BJPs success.
News & Media
The bond between paper and audience is one key reason for its success.
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
Expert writing Tips
Best practice
Pair "key reason for" with strong evidence or data to support your claim, enhancing the credibility of your argument.
Common error
Avoid using "key reason for" repeatedly within a short paragraph or passage. Vary your language by using synonyms like "primary cause", "main factor", or rephrasing the sentence to maintain reader engagement and avoid sounding monotonous.
Source & Trust
85%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "key reason for" functions as a causal indicator, introducing the most important explanation or cause for a particular situation or phenomenon. As Ludwig AI explains, it highlights the primary driver behind an event or outcome.
Frequent in
News & Media
35%
Science
30%
Formal & Business
15%
Less common in
Encyclopedias
7%
Wiki
7%
Reference
6%
Ludwig's WRAP-UP
In summary, "key reason for" is a versatile phrase used to introduce the most important cause or explanation for something. Ludwig AI confirms its correctness and usability in written English. It's commonly found in news, scientific, and formal business contexts. When using this phrase, ensure the reason you provide is indeed the most significant and support it with evidence. Avoid overusing it in close proximity and consider synonyms to maintain reader engagement. By following these guidelines, you can effectively use "key reason for" to enhance the clarity and impact of your writing.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
primary cause of
Focuses on direct causation rather than general reasoning.
main explanation for
Emphasizes the act of explaining something.
the most important factor
Emphasizes importance by direct comparison.
chief factor in
Highlights a contributing element, often in a broader context.
principal motive behind
Implies intention or purpose as the driving force.
central justification for
Suggests a formal defense or rationale.
underlying basis for
Points to a more fundamental or foundational reason.
driving force behind
Highlights the power and energy that motivates something.
fundamental aspect of
Focuses on an essential component or characteristic.
core element of
Stresses that it is a basic and essential part of something.
FAQs
How can I use "key reason for" in a sentence?
The phrase "key reason for" is used to highlight the most important explanation or cause of something. For example: "The "key reason for" the company's success was its innovative marketing strategy."
What are some alternatives to "key reason for"?
You can use alternatives like "primary cause of", "main explanation for", or "chief factor in" depending on the context. Each emphasizes a slightly different aspect of causation or explanation.
Is it correct to say "a key reason is because"?
While commonly used, "a key reason is because" can be redundant. It's generally better to say "the "key reason is"" followed by the reason, or use "a "key reason for"" followed by a noun or gerund.
What's the difference between "key reason for" and "one reason for"?
"Key reason for" implies that the reason is the most important or significant, while "one reason for" suggests that it's just one of several possible reasons.
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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
85%
Authority and reliability
4.5/5
Expert rating
Real-world application tested