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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
Must
Grammar usage guide and real-world examplesUSAGE SUMMARY
The word "must" is a correct and commonly used word in written English.
It is often used to express a requirement or obligation. Example: "You must have a driver's license to operate a motor vehicle."
✓ Grammatically correct
News & Media
Formal & Business
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
"It must be the spirit of the place".
News & Media
"We must show them the multitude of statements of condemnation from British Muslims, show them these men of hate have no place in our mosques or any place of worship, and that they do not speak for Muslims in Britain or anywhere in the world.
News & Media
"We must show our young people, who may be targeted, that extremists have nothing to offer them.
News & Media
We must show them that there are other ways to express disagreement, that their right to do so is dependent on the very freedoms that extremists seek to destroy.
News & Media
You must take legal action now or you may lose the opportunity to do so due to future legal obstacles".
News & Media
These tragedies must end.
News & Media
And as we meet here, we again declare that the regime of Bashar al-Assad must come to an end so that the suffering of the Syrian people can stop and a new dawn can begin.
News & Media
That must not happen".
News & Media
It must be done.
News & Media
That must have hurt.
News & Media
Needs must.
News & Media
Expert writing Tips
Best practice
Employ "must" to indicate a logical conclusion or certainty based on evidence. For example, "The lights are on; someone must be home."
Common error
Avoid using "must" in situations where a softer, more polite request is appropriate. Overusing "must" can sound demanding or impolite. Instead of saying "You must send me the report immediately", consider "Could you please send me the report as soon as possible?"
Source & Trust
94%
Authority and reliability
4.6/5
Expert rating
Real-world application tested
Linguistic Context
The modal verb "must" primarily functions to express obligation, necessity, or strong recommendation. As evidenced by Ludwig, it's used to indicate what is required or essential. Additionally, "must" can express a logical deduction or certainty based on available evidence.
Frequent in
News & Media
60%
Formal & Business
20%
Science
20%
Less common in
Encyclopedias
0%
Wiki
0%
Reference
0%
Ludwig's WRAP-UP
In summary, the modal verb "must" is a versatile word used to express obligation, necessity, or logical deduction. As confirmed by Ludwig, its grammatical status is correct, and it appears very commonly in various contexts, particularly in News & Media and Formal & Business settings. While "must" effectively conveys strong requirements, it's important to be mindful of the tone and consider softer alternatives like "should" or "need to" for more polite requests. With a high expert rating and a strong source quality score, "must" remains a reliable and essential component of the English language.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
have to
Indicates a requirement or obligation, similar to "must" but can also imply external imposition rather than internal necessity.
it is mandatory
Indicates that something is compulsory or obligatory, much like "must" in its authoritative sense.
it is imperative
Highlights the critical or urgent nature of something, mirroring the strong sense of necessity in "must".
need to
Suggests a requirement, but often implies a lesser degree of urgency or obligation than "must".
it is required
States that something is necessary according to a rule or law, similar to one aspect of "must".
it is essential
Emphasizes the importance or necessity of something, conveying a similar level of importance as "must".
ought to
Similar to "should", indicating a moral or practical obligation that is less forceful than "must".
bound to
Expresses a strong likelihood or certainty, similar to one of the inferential uses of "must".
should
Expresses a recommendation or advice, carrying a weaker sense of obligation compared to "must".
certainly
Indicates a high degree of confidence or inevitability, akin to using "must" for deduction.
FAQs
How do I use "must" to show obligation?
Use "must" to express a strong obligation or requirement. For example, "Employees "must attend" the safety training session."
When can "must" indicate a logical conclusion?
"Must" can suggest a logical deduction based on evidence. For example, if you see footprints in the snow, you might say, "Someone "must have walked" here recently."
Is it better to use "must" or "have to"?
Both "must" and "have to" express obligation, but "must" often implies a stronger, more personal sense of necessity or a rule set by the speaker, while "have to" often indicates an external obligation or law.
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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
94%
Authority and reliability
4.6/5
Expert rating
Real-world application tested