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Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
I certain that
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "I certain that" is not correct in English.
Did you mean "I am certain that"? You can use the corrected phrase when expressing confidence or assurance about something. Example: "I am certain that we will meet the project deadline."
⚠ May contain grammatical issues
Alternative expressions(20)
I am sure that
I believe that
I am certain that
I am convinced that
I am positive that
I feel certain that
I have no doubt that
I can assure you that
I am of the opinion that
I confident that
I ascertained that
I clear that
I convinced that
I estimated that
I determined that
I selected that
I precise that
I sure that
I individuals that
I optimistic that
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
7 human-written examples
Am I certain that this second round will lead Egypt to true democracy?
News & Media
Nor – which is perhaps more to the point – am I certain that leaving would necessarily be such a bad thing.
News & Media
I'm not certain that Banged Up will have the policy impact that all of us involved with the programme might have hoped for, nor am I certain that penal abolition is just around the corner.
News & Media
Am I certain that the current spate of approvals aren't just the result of things going remarkably well for a while?
News & Media
"Am I certain that it's there?
News & Media
Am I certain that the Obama administration won't play favorites with this money?
News & Media
Human-verified similar examples from authoritative sources
Similar Expressions
53 human-written examples
2) Is it certain that A and D are apo?
Science
Is it certain that all of its effect is due to increased levels of sei?
Science
Is it certain that this anti-P Ab only recognizes the fully tetra-phosphorylated C-terminus?
Science
I feel certain that will help.
News & Media
'I'm certain that's true.
News & Media
Expert writing Tips
Best practice
Always use the correct grammatical form "I am certain that" when you want to express assurance or confidence in a statement. Ensure the inclusion of the auxiliary verb "am" for proper sentence construction.
Common error
A common mistake is to omit the auxiliary verb "am" and write "I certain that". This is grammatically incorrect. Always include "am" to form a complete and correct sentence: "I am certain that."
Source & Trust
60%
Authority and reliability
1/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "I certain that" is grammatically incomplete. It requires the auxiliary verb "am" to function as a complete sentence. As Ludwig AI points out, this phrase is incorrect and needs correction to convey the intended meaning of certainty.
Frequent in
Science
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News & Media
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Formal & Business
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Less common in
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News & Media
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Formal & Business
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Ludwig's WRAP-UP
In summary, the phrase "I certain that" is grammatically incorrect due to the absence of the auxiliary verb "am". The correct form, "I am certain that", should be used to express certainty, assurance, or a strong belief. As Ludwig AI indicates, this correction is essential for proper sentence construction and effective communication. While there are no examples of the incorrect phrase in the provided data, numerous alternatives, such as "I am sure that" and "I believe that", can be used to convey similar meanings.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
I am certain that
Adds the necessary verb "am" to make the sentence grammatically correct.
I know for certain that
Highlights the knowledge aspect of certainty, implying confirmed information.
I am sure that
Replaces "certain" with "sure", providing a similar meaning with slightly less formality.
I am positive that
Uses "positive" as a synonym for "certain", conveying a strong sense of assurance.
I feel certain that
Emphasizes the feeling of certainty, suggesting an intuitive sense rather than factual knowledge.
I have no doubt that
Indicates a lack of doubt, implying a high degree of certainty.
I am convinced that
Indicates a strong belief based on evidence or persuasion, rather than simple certainty.
I can assure you that
Offers a direct assurance, often used to reassure someone else.
I believe that
Expresses a belief or opinion, which may be based on less solid evidence than certainty.
I am of the opinion that
Formally expresses a belief or judgment, often based on careful consideration.
FAQs
What is the correct way to say "I certain that"?
The correct way to express certainty is to say "I am certain that". The auxiliary verb "am" is necessary for proper grammar.
What can I say instead of "I certain that"?
You can use alternatives like "I am sure that", "I believe that", or "I am convinced that" depending on the context and the level of certainty you want to convey.
Which is correct, "I certain that" or "I am certain that"?
"I am certain that" is the correct form. "I certain that" is grammatically incorrect due to the missing auxiliary verb "am".
What's the difference between "I certain that" and "I am certain that"?
"I certain that" is grammatically incorrect. "I am certain that" is the grammatically correct way to express a feeling of certainty. The inclusion of the verb "am" is essential for proper sentence structure.
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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
60%
Authority and reliability
1/5
Expert rating
Real-world application tested