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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
reason why
Grammar usage guide and real-world examplesUSAGE SUMMARY
"reason why" is a correct and usable phrase in written English.
It is used to explain the basis for a certain opinion or thought. For example, "The reason why I love this movie is the underlying theme of family."
✓ Grammatically correct
News & Media
Science
Wiki
Alternative expressions(20)
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
59 human-written examples
Any reason why?
News & Media
The reason why is uncertain.
News & Media
There's no reason why not".
News & Media
"There's no reason why.
News & Media
Here's one reason why.
News & Media
And the reason why?
News & Media
"That is the reason why.
News & Media
Absolutely no reason why not.
News & Media
The reason why may surprise you.
News & Media
Yours is not to reason why.
News & Media
And neuroscientists know the reason why.
News & Media
Expert writing Tips
Best practice
When using "reason why", ensure it's followed by a complete clause to clearly articulate the explanation. Avoid redundancy by not repeating the word "reason" unnecessarily (e.g., avoid "the reason why is because").
Common error
Avoid using phrases like "the reason why is because" as it's repetitive. Instead, choose either "the reason is" or "why" followed by your explanation to maintain conciseness.
Source & Trust
84%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "reason why" functions as a causal connector, introducing an explanation or justification. It sets the stage for clarifying the basis or motive behind a particular situation or event. Ludwig AI confirms that this phrase is widely recognized and accepted in English.
Frequent in
News & Media
65%
Science
15%
Wiki
10%
Less common in
Formal & Business
5%
Encyclopedias
3%
Reference
2%
Ludwig's WRAP-UP
In summary, the phrase "reason why" serves as a causal connector used to introduce an explanation or justification. Ludwig AI identifies it as grammatically correct and very commonly used. While versatile, it's best to avoid redundancy such as "the reason why is because". Alternatives like "cause for" or "explanation for" can provide similar meanings with slight variations. Its frequent appearance in News & Media sources and widespread acceptance highlight its utility in providing clarity and understanding across various contexts. Remember to follow best practices and conciseness, as its clarity may depend on your attention to wording.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
the why
A shortened, more direct way of asking for the reason.
explanation for
Highlights the act of clarifying or providing understanding.
cause for
Emphasizes the underlying cause or origin of something.
justification for
Focuses on providing a valid reason or defense for an action or belief.
grounds for
Suggests the basis or foundation on which something is based.
the cause of
Focuses specifically on the event or circumstance that produces an effect.
rationale behind
Indicates the logical basis or principle that supports something.
basis for
Highlights the fundamental support or reason for something.
purpose of
Emphasizes the intended aim or goal behind something.
source of
Highlights the origin or starting point of something.
FAQs
How can I use "reason why" in a sentence?
Use "reason why" to introduce an explanation or cause. For example, "The "reason why" she succeeded was her determination".
What are some alternatives to "reason why"?
You can use alternatives such as "cause for", "explanation for", or "justification for", depending on the specific context.
Is it grammatically correct to say "the reason why is because"?
While commonly used, "the reason why is because" is considered redundant. A more concise phrasing would be "the reason is" or simply "why" followed by the explanation.
What's the difference between "reason why" and "the reason for"?
"Reason why" typically introduces a clause explaining something, whereas "the reason for" is followed by a noun or noun phrase. For instance, "the "reason why" I'm late is that the traffic was bad" versus "the reason for my lateness is the traffic".
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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
84%
Authority and reliability
4.5/5
Expert rating
Real-world application tested