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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 be prohibited
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "must be prohibited" is correct and usable in written English.
It can be used to indicate that something is required to be banned or not allowed, often in formal or legal contexts. Example: "In order to maintain a safe environment, any form of harassment must be prohibited."
✓ Grammatically correct
News & Media
Science
Formal & Business
Alternative expressions(20)
should be forbidden
is not allowed
should be prohibited
is strictly forbidden
cannot be permitted
is impermissible
is out of the question
is ruled out
is off-limits
must be prevented
must be cut
must be prosecuted
must be identified
must be tackled
must be researched
must be eliminated
must be thrilled
must be overturned
must be breached
must be addressed
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
33 human-written examples
Insurance companies must be prohibited from discriminating based on medical history — a prohibition that must include preventing them from issuing bare-bones policies that will appeal only to those in good health — but that won't do the job by itself.
News & Media
A majority of nations believe that nuclear weapons are unacceptable and must be prohibited.
News & Media
Unilateral action must be prohibited and geo-engineering must be outlawed as a form of aggression.
News & Media
Firing gas canisters or grenades directly into a crowd or toward individuals must be prohibited.
News & Media
While adults shouldn't needlessly expose themselves to this potentially deadly radiation, children must be prohibited from exposure to this cancer-causing agent.
News & Media
Dual tracking must be prohibited, and if foreclosure is unavoidable, servicers must provide borrowers with verification of their legal right to foreclose before starting the process.
News & Media
Human-verified similar examples from authoritative sources
Similar Expressions
27 human-written examples
In addition, digital learning options must not be prohibited.
News & Media
What worked for the US, China and South Korea must not be prohibited by the WTO.
News & Media
Note: Expenditures on a non-federal sponsored project must not be prohibited by the sponsor in its terms and conditions or by University policy.
Academia
That means, for example, that experiments involving the supply of heroin on medical prescription must not just be prohibited by national authorities out of hand.
Formal & Business
Regarding content, the speech – in order to be prohibited – must be 'contemptuous, hateful and malicious'; specifying that it particularly targets expressions of 'classical' biological racism.
News & Media
Expert writing Tips
Best practice
When using "must be prohibited", ensure the context clearly defines the authority enforcing the prohibition, enhancing the statement's clarity and impact.
Common error
Avoid using "must be prohibited" in casual conversation; opt for more relaxed alternatives like "is not allowed" or "is off-limits" to maintain a natural tone.
Source & Trust
84%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "must be prohibited" functions as a modal passive construction, expressing a strong obligation that something is not allowed. Ludwig AI confirms this phrase is used to enforce rules or regulations, as seen in examples like, "Firing gas canisters or grenades directly into a crowd or toward individuals must be prohibited."
Frequent in
News & Media
37%
Science
33%
Formal & Business
15%
Less common in
Academia
8%
Wiki
7%
Ludwig's WRAP-UP
In summary, the phrase "must be prohibited" is a modal passive construction used to express a strong and non-negotiable ban. As confirmed by Ludwig AI, it is grammatically correct and frequently appears in formal contexts such as news reports, scientific articles, and official documents. To ensure clarity and appropriateness, avoid its overuse in casual settings, and always define the enforcing authority when using the phrase. Related phrases like "should be forbidden", "needs to be banned", and "is not allowed" can provide suitable alternatives depending on the context and desired tone.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
should be forbidden
Replaces "must" with "should", softening the obligation but retaining the sense of prohibition.
needs to be banned
Uses "needs to be" instead of "must be", and "banned" instead of "prohibited", offering a more direct and forceful tone.
is strictly forbidden
Emphasizes the prohibition with "strictly", reinforcing the mandatory nature of the ban.
is not allowed
Offers a simpler and more straightforward way to express the prohibition, suitable for less formal contexts.
cannot be permitted
Replaces "must" with "cannot", highlighting the impossibility of permission.
is impermissible
Uses the single word "impermissible" to convey that something is not allowed, suitable for formal contexts.
is out of the question
Expresses a strong rejection or prohibition, often used in informal settings.
is ruled out
Suggests that something has been officially excluded or prohibited.
is off-limits
Informally indicates that something is forbidden or restricted.
is under embargo
Specifically indicates a legal or official prohibition, often in trade or information contexts.
FAQs
How can I use "must be prohibited" in a sentence?
Use "must be prohibited" to express that something is absolutely not allowed or permitted. For instance, "The use of mobile phones during the exam "must be prohibited"."
What are some alternatives to "must be prohibited"?
Alternatives include "should be forbidden", "needs to be banned", or "is not allowed", depending on the formality and strength of the prohibition you wish to convey.
When is it appropriate to use "must be prohibited"?
"Must be prohibited" is best suited for formal or official contexts, such as legal documents, policy statements, or official announcements, where a strict ban is being communicated.
What is the difference between "must be prohibited" and "should be prohibited"?
"Must be prohibited" indicates a strict, non-negotiable ban, whereas "should be prohibited" suggests a recommendation or strong suggestion for a ban, leaving room for potential exceptions or flexibility.
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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