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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
uncertain of
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "uncertain of" is correct and usable in written English.
It can be used when expressing doubt or lack of confidence about something specific. Example: "She was uncertain of her decision to move to a new city for work."
✓ Grammatically correct
News & Media
Encyclopedias
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
57 human-written examples
Tim was uncertain of what to do.
News & Media
She seems, now, uncertain of its future.
News & Media
They seemed uncertain of themselves.
News & Media
Uncertain of her own health.
News & Media
Your mind is very uncertain of time.
News & Media
It's messy, endless and uncertain of success.
News & Media
Even now we're uncertain of its size.
News & Media
(He's still uncertain of all the legalities).
News & Media
Yates seemed uncertain of where to go to eat.
News & Media
The Army is still uncertain of the toll.
News & Media
He is not uncertain of what he thinks.
News & Media
Expert writing Tips
Best practice
Use "uncertain of" when you want to express a lack of confidence or knowledge about a specific fact, outcome, or situation. Ensure the object of uncertainty is clearly defined to avoid ambiguity.
Common error
Avoid using "uncertain of" with overly broad or undefined subjects. For instance, instead of saying "He was uncertain of things", specify what he was uncertain about to provide clarity and impact.
Source & Trust
88%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "uncertain of" functions as a predicate adjective describing a state of doubt or lack of conviction. As Ludwig AI confirms, it is a correct and usable expression. Examples show it modifying individuals or entities, indicating their state of uncertainty.
Frequent in
News & Media
60%
Encyclopedias
20%
Wiki
10%
Less common in
Science
5%
Formal & Business
3%
Reference
2%
Ludwig's WRAP-UP
In summary, "uncertain of" is a versatile and grammatically sound phrase used to express a state of doubt or lack of conviction. Ludwig AI confirms its correctness and usability. It is frequently found in news and media, encyclopedias, and wiki sources, indicating its widespread acceptance across various registers. For alternative phrasing, consider "unsure about", or "doubtful regarding", depending on the nuance you want to convey. When using "uncertain of", ensure the subject of uncertainty is clearly defined to avoid ambiguity.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
unsure about
Emphasizes a lack of sureness or confidence about something.
doubtful regarding
Highlights skepticism or disbelief concerning a particular matter.
questioning concerning
Suggests an active process of inquiry and uncertainty about something.
dubious about
Implies a degree of suspicion or reservation about something.
hesitant regarding
Indicates a pause or reluctance due to uncertainty.
wavering on
Conveys indecision or fluctuation in opinion.
unsettled about
Suggests a lack of resolution or peace of mind regarding something.
in doubt about
Highlights the presence of uncertainty or skepticism.
undecided on
Focuses on the lack of a firm decision regarding a choice or option.
speculating about
Suggests forming a theory or conjecture without firm evidence.
FAQs
How can I use "uncertain of" in a sentence?
You can use "uncertain of" to express a lack of confidence or knowledge about something. For example, "She was "uncertain of" the correct answer" or "They were "uncertain of" the outcome of the experiment".
What are some alternatives to "uncertain of"?
Some alternatives to "uncertain of" include "unsure about", "doubtful regarding", or "questioning concerning". The best choice depends on the specific context and the nuance you want to convey.
Is it better to say "uncertain of" or "unsure of"?
Both "uncertain of" and "unsure of" are grammatically correct and convey a similar meaning. "Unsure of" is slightly more informal, while "uncertain of" can sound more formal. Choose the one that best fits the tone of your writing.
What's the difference between "uncertain of" and "doubtful about"?
"Uncertain of" generally implies a lack of knowledge or confidence, while "doubtful about" suggests skepticism or disbelief. You might be "uncertain of" the weather forecast, but "doubtful about" someone's honesty.
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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
88%
Authority and reliability
4.5/5
Expert rating
Real-world application tested