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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 retained
Grammar usage guide and real-world examplesUSAGE SUMMARY
"must be retained" is a perfectly correct and usable phrase in written English.
You can use it when you want to express that something needs to be held onto, kept, or maintained. For example: "All of our cultural heritage sites must be retained for future generations to experience."
✓ Grammatically correct
Academia
News & Media
Science
Alternative expressions(20)
needs to be preserved
should be maintained
is essential to keep
needs to be conserved
should be safeguarded
must be nurtured
must be cut
must be identified
must be tackled
must be breached
must be expected
must be done
must be scared
must be confused
must be told
must be found
must be tightened
must be annihilated
must be shaken
must be relieved
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
§ 98.397 Records that must be retained.
Academia
§ 98.417 Records that must be retained.
Academia
§ 98.37 Records that must be retained.
Academia
§ 98.347 Records that must be retained.
Academia
§ 98.387 Records that must be retained.
Academia
But an advocate of open government must be retained.
News & Media
EPCs are required under European law, so they must be retained.
News & Media
If we are to see these jobs and investment realised, confidence must be retained.
News & Media
The E component represents random error and must be retained in all models40.
Science & Research
In all cases, the original data and materials must be retained at Yale.
Academia
Recordkeeping for VFD can be either written or electronic and must be retained for 2 years.
Academia
Expert writing Tips
Best practice
When using "must be retained", ensure the context clearly indicates what needs to be kept and why. Providing a specific reason enhances the clarity and impact of your statement.
Common error
Avoid using "must be retained" without providing a clear justification. Overusing the phrase without explaining its importance can weaken its impact and make your writing sound repetitive.
Source & Trust
84%
Authority and reliability
4.6/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "must be retained" functions as a modal passive construction. It expresses a strong obligation or necessity for something to be kept or preserved. Ludwig examples show it in legal, scientific, and general contexts, indicating its broad applicability. Ludwig AI confirms that it is grammatically correct.
Frequent in
Academia
30%
Science
30%
News & Media
40%
Less common in
Wiki
3%
Formal & Business
0%
Encyclopedias
0%
Ludwig's WRAP-UP
In summary, "must be retained" is a grammatically correct and commonly used phrase that conveys a strong obligation to keep or preserve something. Ludwig AI confirms its validity and wide applicability. It is frequently found in academic, scientific, and news contexts, reflecting its use in situations where precision and clarity are essential. When using this phrase, make sure to clearly state what needs to be retained and why to maximize its impact. Alternatives include "needs to be preserved" or "should be maintained", offering subtle variations in emphasis. By understanding its nuances and appropriate contexts, you can effectively incorporate "must be retained" into your writing.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
needs to be preserved
Emphasizes maintaining something in its original condition.
should be maintained
Suggests a recommendation to keep something in good order.
has to be kept
Indicates a necessity to hold onto something.
is required to be preserved
Highlights a formal obligation to maintain something.
is essential to keep
Stresses the importance of maintaining something.
needs to be conserved
Focuses on careful preservation and avoidance of waste or depletion.
ought to be upheld
Suggests a moral or ethical obligation to maintain something.
should be safeguarded
Emphasizes protecting something from harm or loss.
is important to maintain
Underlines the significance of keeping something in a specific condition.
is vital to preserve
Highlights the critical importance of maintaining something for its survival or functionality.
FAQs
How to use "must be retained" in a sentence?
Use "must be retained" to express that something needs to be kept or preserved. For example, "All original documents "must be retained" for audit purposes".
What can I say instead of "must be retained"?
You can use alternatives like "needs to be preserved", "should be maintained", or "has to be kept" depending on the context.
Which is correct, "must be retained" or "should be retained"?
"Must be retained" implies a stronger obligation than "should be retained". Use "must" when there is a firm requirement and "should" when it's a recommendation.
What's the difference between "must be retained" and "needs to be retained"?
"Must be retained" typically indicates a more formal or legal requirement, whereas "needs to be retained" can convey a general necessity. The best choice depends on the tone and context of your writing.
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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
4.6/5
Expert rating
Real-world application tested