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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
it must be true
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase 'it must be true' is correct and can be used in written English.
It is a way of expressing certainty about a statement. For example, you could say, "The children had never seen snow before, so it must be true that they were amazed."
✓ Grammatically correct
News & Media
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
Chambers's account of what happened next sounds so raw in its telling it must be true.
News & Media
It must be true.
News & Media
So it must be true.
News & Media
The silence is ear-shattering, so it must be true.
News & Media
(It's all over the Internet, so it must be true).
News & Media
Finchy's doing the voice over, so it must be true.
News & Media
The advice sounds so reasonable it must be true.
News & Media
So it must be true: he was past it.
News & Media
And if Jeter says so, it must be true.
News & Media
That settles it, it must be true - it's in Heat!
News & Media
It was so specific we thought it must be true.
News & Media
Expert writing Tips
Best practice
Be mindful of the context. While generally acceptable, overuse can make your writing sound naive or overly simplistic. Consider stronger or more nuanced phrases for academic or formal settings.
Common error
Avoid using "it must be true" as a substitute for critical thinking or verification. Always strive to confirm information independently, especially in formal or academic writing, before asserting its truth based on assumptions.
Source & Trust
92%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "it must be true" functions as an epistemic modal, indicating the speaker's assessment of the likelihood or certainty of a proposition. As Ludwig AI states, it expresses certainty about a statement. The examples show it being used to convey a belief based on available information or common knowledge.
Frequent in
News & Media
98%
Science
1%
Formal & Business
1%
Less common in
Encyclopedias
0%
Wiki
0%
Reference
0%
Ludwig's WRAP-UP
In summary, "it must be true" is a common phrase used to express a conclusion based on evidence or general knowledge. As Ludwig AI points out, it conveys a sense of certainty. While grammatically correct and widely used, its appropriateness depends on the context. It's most frequent in News & Media but less suitable for formal academic writing where direct evidence and rigorous analysis are expected. Related phrases like "it has to be true" or "it is undoubtedly true" can offer variations in emphasis and formality. Always ensure the conclusion is reasonably supported to avoid misuse of the phrase.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
it has to be true
Changes "must be" to "has to be", suggesting a slightly stronger sense of obligation or inevitability regarding the truth.
it is undoubtedly true
Adds "undoubtedly" to emphasize the lack of doubt or question regarding the truth.
it is definitely true
Replaces "must be" with "is definitely", offering a more direct assertion of truth.
it is certainly true
Similar to "definitely true", but with a slightly more formal tone.
it is assuredly true
Uses "assuredly" to convey a sense of guaranteed truth, which is more emphatic and less common.
there's no doubt it's true
Shifts the structure to emphasize the absence of doubt about the truth.
it stands to reason that it's true
Implies that the truth is a logical conclusion based on available information.
it is logically true
Highlights that the truth stems from a coherent and rational line of reasoning.
it's verifiably true
Indicates that the truth can be confirmed or proven through evidence.
the evidence suggests it's true
Attributes the assertion of truth to the support of existing evidence, framing the truth as an informed inference.
FAQs
How can I use "it must be true" in a sentence?
Use "it must be true" to express a conclusion based on available evidence or information. For example, "She studied for weeks; "it must be true" she will ace the exam".
What are some alternatives to "it must be true"?
You can use alternatives like "it has to be true", "it is certainly true", or "it is undoubtedly true" depending on the context and the degree of certainty you want to convey.
When is it inappropriate to use the phrase "it must be true"?
It is best to avoid using "it must be true" in formal writing or academic contexts where a more rigorous and evidence-based approach is expected. Relying on this phrase may suggest a lack of critical analysis.
What's the difference between "it must be true" and "it is true"?
"It is true" states a fact directly, while "it must be true" implies a conclusion drawn from evidence or reasoning. "It must be true" suggests a level of inference rather than a direct assertion of fact. The choice depends on whether you are stating a known fact or making an informed deduction.
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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
92%
Authority and reliability
4.5/5
Expert rating
Real-world application tested