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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
to be kept
Grammar usage guide and real-world examplesUSAGE SUMMARY
"to be kept" is correct and usable in written English.
You can use it when referring to something that needs to be remembered, stored, or maintained. For example: "The passwords used to access the system must be kept secure at all times."
✓ Grammatically correct
News & Media
Science
Formal & Business
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
Secrets had to be kept.
News & Media
Expectations have to be kept realistic.
News & Media
Things had to be kept moving.
News & Media
Disorder had to be kept at bay.
Encyclopedias
These places need to be kept alive.
News & Media
She didn't want to be kept, anywhere.
News & Media
The two need to be kept separate.
News & Media
The programme framework has to be kept".
News & Media
"Traffic needs to be kept moving".
News & Media
There were still secrets to be kept.
News & Media
Citizens were to be kept at bay.
News & Media
Expert writing Tips
Best practice
When using "to be kept", ensure the sentence clearly indicates who or what is responsible for maintaining or preserving the item or information.
Common error
Avoid replacing the passive construction "to be kept" with an active voice construction using 'keep' when the passive voice is more appropriate. For example, instead of "They must keep the data secret", using "The data has to be kept secret" might be more fitting if you want to focus on the data's state rather than the actor.
Source & Trust
82%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "to be kept" functions as part of an infinitive construction, often appearing in passive voice sentences. As shown in Ludwig, it indicates a requirement or necessity for something to remain in a specified condition or state. For example, "Secrets had to be kept."
Frequent in
News & Media
40%
Science
25%
Formal & Business
15%
Less common in
Wiki
10%
Encyclopedias
5%
Reference
5%
Ludwig's WRAP-UP
In summary, "to be kept" is a versatile phrase used to indicate a necessity for maintaining or preserving something in a particular state. Ludwig AI confirms its grammatical correctness and common usage across various contexts, including news, science, and business. When writing, remember that the phrase's formality can range from neutral to professional, depending on the context. Be mindful to avoid replacing the passive construction of "to be kept" with an active voice construction using 'keep' if the passive voice is more appropriate to highlight who or what is responsible for maintaining or preserving the item or information.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
to be maintained
Focuses on the act of preserving the condition of something.
to be preserved
Emphasizes protecting something from decay or damage.
to be retained
Highlights the act of keeping something in one's possession or memory.
to be safeguarded
Implies protecting something from potential harm or threat.
to be protected
Stresses the action of shielding something from danger.
to be conserved
Focuses on the careful use of resources to prevent depletion.
to be stored
Highlights the act of placing something in a specific location for future use.
to be held
Emphasizes keeping something in a particular state or condition.
to be upheld
Implies maintaining a principle or standard.
to be sustained
Focuses on supporting or maintaining something over a period of time.
FAQs
How can I use "to be kept" in a sentence?
Use "to be kept" when you want to express that something needs to be maintained or preserved in a certain state or condition. For example, "The samples need "to be kept" refrigerated."
What are some alternatives to the phrase "to be kept"?
You can use alternatives such as "to be maintained", "to be preserved", or "to be retained" depending on the specific context.
Is there a difference between saying 'must be kept' and 'needs to be kept'?
While both phrases convey a necessity, 'must be kept' often implies a stronger obligation or requirement compared to 'needs to be kept'. The choice depends on the level of emphasis you want to convey.
How do I ensure something "is to be kept" confidential?
When indicating something is ""to be kept" confidential", explicitly state the requirement and any consequences for failing to do so. For example, "All project documents are "to be kept" confidential, and any unauthorized disclosure will result in disciplinary action."
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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
82%
Authority and reliability
4.5/5
Expert rating
Real-world application tested