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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
main reason
Grammar usage guide and real-world examplesUSAGE SUMMARY
"main reason" is correct and usable in written English.
You can use it when you want to emphasize an important idea or point that explains a situation or an action. For example, "The main reason I decided to go to the store was because I needed more ingredients for dinner."
✓ Grammatically correct
News & Media
Academia
Alternative expressions(20)
primary cause
key factor
principal factor
chief factor
key reason
major contributing factor
fundamental reason
underlying reason
core motive
prime driver
primary reason
main consequence
major contributor
leading reason
prominent reason
principal reason
central reason
salient reason
predominant reason
substantial cause
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
60 human-written examples
The main reason?
News & Media
"That's the main reason.
News & Media
The main reason is space.
News & Media
The main reason was clear.
News & Media
The main reason is cost.
News & Media
The main reason is Russia.
News & Media
The main reason is bureaucracy.
News & Media
One main reason is uncertainty.
News & Media
Demography is the main reason.
News & Media
But the main reason is politics.
News & Media
Not the main reason the Dutch lost.
News & Media
Expert writing Tips
Best practice
Use "main reason" to introduce the most important factor in a complex situation, helping your audience focus on what matters most.
Common error
Avoid using "main reason" repeatedly within a short passage. Vary your language by using synonyms like "primary cause", "key factor", or "principal reason" to maintain reader engagement and avoid redundancy.
Source & Trust
89%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "main reason" functions as a noun phrase identifying the primary cause or justification for a particular situation or event. As confirmed by Ludwig AI, it is considered grammatically correct and widely used in the English language.
Frequent in
News & Media
79%
Academia
13%
Formal & Business
4%
Less common in
Science
2%
Wiki
1%
Reference
1%
Ludwig's WRAP-UP
The phrase "main reason" is a common and grammatically sound way to express the primary cause or justification for something. Ludwig AI confirms its acceptability and widespread use. Analysis of the examples shows that it's most frequently used in news and media, followed by academic writing. When using "main reason", ensure that it directly relates to the situation you are describing and consider using synonyms to avoid redundancy. Remember that while similar, "main reason" carries a stronger emphasis than simply stating "a reason".
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
primary cause
Focuses on causality, highlighting the origin or initial trigger of an event.
chief factor
Emphasizes the significance of a particular element in contributing to a result.
principal factor
Stresses the dominance of one element over others in influence or importance.
key reason
Highlights the essential nature of a reason, suggesting it unlocks understanding.
central cause
Indicates a core reason around which other factors revolve.
major contributing factor
Acknowledges that multiple factors exist, but this one is the most significant.
fundamental reason
Points to the base or root cause, implying it is the foundation for everything else.
underlying reason
Suggests a less obvious, but ultimately more important, cause.
core motive
Highlights the driving intention or purpose behind an action.
prime driver
Implies that this reason is the force that propels a particular outcome.
FAQs
How can I use "main reason" in a sentence?
You can use "main reason" to highlight the primary cause or justification for something. For example: "The "main reason" for the delay was the unexpected weather conditions".
What are some alternatives to "main reason"?
Alternatives include "primary cause", "key factor", or "principal factor". The best choice depends on the specific context.
Is it redundant to say "the main reason is because"?
While common, "the main reason is because" can be considered slightly redundant. It's often more concise and grammatically sound to say "the "main reason" is" or "the reason is because".
What is the difference between "main reason" and "a reason"?
"Main reason" indicates the most important or primary cause, while "a reason" simply suggests one of potentially many causes. "The "main reason"" implies greater significance than just "a reason".
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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
89%
Authority and reliability
4.5/5
Expert rating
Real-world application tested