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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
is not functioning correctly
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "is not functioning correctly" is correct and usable in written English.
You can use it when describing a device, system, or process that is not operating as intended. Example: "The printer is not functioning correctly, and we need to troubleshoot the issue."
✓ Grammatically correct
News & Media
Science
Wiki
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
5 human-written examples
But when your mind is not functioning correctly, you're not thinking clearly, you lose that opportunity," he said.
News & Media
"They have to understand that if discomfort or pain is being suffered, it means that something is not functioning correctly.
News & Media
The idea is that whether someone's body is not functioning correctly is a separate question from whether it is bad to be like that.
Science
The gapping of the market to this extent is a symptom that our market is not functioning correctly, says Larry Tabb, CEO of the Tabb Group, and an expert consultant on electronic trading.
News & Media
Regardless of their hardest attempts they and their families were constantly caught in this cycle -- a cycle that our country is complicit in creating, supporting and allowing to continue even when it is not functioning correctly.
News & Media
Human-verified similar examples from authoritative sources
Similar Expressions
55 human-written examples
Dr. Gary I. Wadler, an associate professor of medicine at New York University and a member of the World Anti-Doping Agency, said if a pituitary gland was not functioning correctly, a deficiency of H.G.H. could occur in the body.
News & Media
Research has shown that most existing fishways in China are not functioning correctly.
Science
That would be when Apple revealed to iPhone 6 owners that their batteries were not functioning correctly and that they'd have to pay for a replacement if they wanted full functionality.
News & Media
Finally, inspection of the tuned mass dampers installed on the bridge to reduce the level of vibration in the first mode showed that they were not functioning correctly after the last event.
In February it was reported that a Notice to Airmen had been issued stating that aircraft coming from the Continent in conditions of poor visibility in which the radio was not functioning correctly should land at Lympne, where repair facilities were available.
Wiki
They will cause stalling as well if they are not functioning correctly.
Wiki
Expert writing Tips
Best practice
When describing a complex system, specify which component "is not functioning correctly" to avoid ambiguity.
Common error
Avoid using "is not functioning correctly" as a catch-all phrase. Provide specific details about the observed malfunction for clearer communication.
Source & Trust
76%
Authority and reliability
4.1/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "is not functioning correctly" serves as a descriptive statement, indicating that a particular entity (whether a device, system, or process) is not operating as intended or designed. Ludwig AI indicates this phrase is correct and usable in written English.
Frequent in
News & Media
40%
Science
33%
Wiki
27%
Less common in
Formal & Business
0%
Encyclopedias
0%
Reference
0%
Ludwig's WRAP-UP
The phrase "is not functioning correctly" is a grammatically correct and usable expression to describe something that is not working as intended, as indicated by Ludwig. It is most frequently found in News & Media, Science, and Wiki contexts. While the phrase is generally neutral, it can be made more specific by identifying the component that is malfunctioning. Alternatives like "is malfunctioning", "is not operating properly", and "is out of order" can be used depending on the situation. When writing, avoid overgeneralization and provide specific details about the malfunction to ensure clarity.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
is malfunctioning
Single word replacement for a more concise expression of the same meaning.
is not operating properly
Replaces "functioning" with "operating" and "correctly" with "properly", maintaining similar meaning.
is not working as expected
Shifts focus to the expected outcome rather than the process itself.
is out of order
A more general term, often used for machines or systems that are temporarily unusable.
is defective
Implies a fault in the manufacturing or design of something.
is impaired
Suggests that the functionality is reduced or weakened, but not completely absent.
is not up to par
Indicates that something is below the expected standard or quality.
is acting up
Informal way to say that something is behaving strangely or unpredictably.
is on the blink
Informal way to say that something, usually electrical, is working intermittently or unreliably.
has gone awry
Suggests that something has deviated from its intended course or function.
FAQs
What does "is not functioning correctly" mean?
It means something isn't working as it should or as intended. It implies a deviation from the expected or normal operation.
What can I say instead of "is not functioning correctly"?
You can use alternatives like "is malfunctioning", "is not operating properly", or "is out of order" depending on the context.
Is "is not functioning correctly" formal or informal?
It's generally considered neutral and can be used in both formal and informal contexts. However, more technical or precise language might be preferred in highly formal situations.
How to use "is not functioning correctly" in a sentence?
You can use it to describe anything that isn't working as expected. For example, "The printer "is not functioning correctly", so I can't print the document."
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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
76%
Authority and reliability
4.1/5
Expert rating
Real-world application tested