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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
What is the reason
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "What is the reason" is correct and usable in written English.
You can use it when asking for an explanation or justification for something. Example: "What is the reason for the delay in the project timeline?"
✓ Grammatically correct
News & Media
Science
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
What is the reason for that?
News & Media
What is the reason for this development?
News & Media
What is the reason for the disparity?
News & Media
What is the reason behind this or that death?
News & Media
What is the reason for Woman B's punishment?
News & Media
What is the reason for this glut of exits?
News & Media
What is the reason for the psychedelic movement in Wales?
News & Media
What is the reason you stopped McLovin' it?
News & Media
What is the reason for such apparent national narcissism?
News & Media
"What is the reason you chose our building?" the guard said.
News & Media
What is the reason for this continuing rivalry?
News & Media
Expert writing Tips
Best practice
Use "What is the reason" to directly and clearly inquire about the cause or justification for a specific event, action, or decision. This phrase is suitable for both formal and informal contexts.
Common error
Avoid using "What is the reason" repeatedly in the same paragraph or conversation. Vary your phrasing by using alternatives like "Why is that?", "What's the explanation?", or "What prompted this?" to maintain reader engagement and avoid sounding repetitive.
Source & Trust
86%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "What is the reason" functions as an interrogative expression, specifically used to elicit an explanation or cause for a particular event, situation, or decision. As Ludwig AI explains, this phrase is grammatically correct and widely applicable.
Frequent in
News & Media
37%
Science
36%
Formal & Business
10%
Less common in
Academia
0%
Encyclopedias
0%
Wiki
0%
Ludwig's WRAP-UP
In summary, the phrase "What is the reason" is a grammatically sound and frequently used interrogative expression aimed at eliciting explanations or causes. As confirmed by Ludwig AI, it is widely employed across diverse contexts, particularly in news and scientific domains. While suitable for both formal and informal communication, varying the phrasing with alternatives like "Why is that?" or "What's the explanation?" can enhance writing. Its neutral register and consistent function make it a reliable choice for clear and effective inquiries.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
What is the explanation
Asks for a detailed account of why something happened.
What is the cause
Focuses specifically on identifying the direct cause of something.
What's the justification
Demands a valid reason or excuse for an action or decision.
What's the rationale
Inquires about the underlying principles or logic behind a decision or action.
What is the basis
Seeks the fundamental grounds or justification for something.
On what grounds
Asks for the specific basis or reasons upon which something is based.
Why is that
This is a more concise and informal way to ask for the reason.
What prompted this
Inquires about the event or situation that triggered a particular action.
Why did this happen
Directly asks for the cause or reason behind an event.
What is the purpose
Explores the intended aim or goal behind an action or decision.
FAQs
How can I rephrase "What is the reason" for variety?
Alternatives include "what is the cause", "what is the explanation", or simply "why is that", depending on the level of formality and context.
Is "What is the reason" appropriate for formal writing?
Yes, "What is the reason" is suitable for formal writing. However, for a more sophisticated tone, consider using alternatives such as "what is the rationale" or "on what grounds".
When is it better to use "Why" instead of "What is the reason"?
Using "Why" is often more direct and concise, suitable for informal situations. "What is the reason" is generally used when seeking a more detailed or formal explanation.
What's the difference between "What is the reason" and "What's the purpose"?
"What is the reason" seeks the cause or explanation for something that has already occurred or is the case. "What's the purpose" /s/what's+the+purpose, on the other hand, inquires about the intended goal or aim of something.
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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
4.5/5
Expert rating
Real-world application tested