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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
I certify
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "I certify" is correct and usable in written English.
You can use it when you want to formally declare or confirm the truth or authenticity of something, often in legal or official contexts. Example: "I certify that the information provided in this document is accurate to the best of my knowledge."
✓ Grammatically correct
News & Media
Science
Wiki
Formal & Business
Alternative expressions(20)
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
25 human-written examples
I have no stake in the sale of the business, nor do I certify that any of the information about the business presented is accurate.
News & Media
As with my earlier posts on businesses for sale, I have no stake in the sale of the business, nor do I certify that any of the information about the business presented is accurate.
News & Media
"I certify a class of all persons and business entities who have accepted Visa and-or MasterCard credit cards and therefore have been required to accept VisaCheck and-or MasterMoney debit cards," Judge Gleeson stated in his opinion.
News & Media
"Your daughter has not signed her name, and the counter-signature on the back of the photograph says 'I certify that this is a true likeness of' but does not say who it is a true likeness of".
News & Media
Before submitting a review, users must check a box stating, "I certify that this review is based on my own experience and is my genuine opinion of this community, and that I have no business relationship with this community and have not been offered any incentive from this community to write this review.
News & Media
Judge Martin Beddoe said: "I certify the benefit to be £32,352,027 and given what I have been told about the issue of Mr Levene's bankruptcy and that the trustee in bankruptcy is confident and has got hold of such assets as were in the possession of Mr Levene in consequence of this offending, it seems to me entirely pragmatic that his assets are seized by the trustee in bankruptcy.
News & Media
Human-verified similar examples from authoritative sources
Similar Expressions
31 human-written examples
But Warrenville was in the town of Ashford, for which I had no guide, and I remember the blissful sense of resolution I felt when I certified that Route 44A crossed Route 89 in the town center, for I had long hypothesized that they might meet there.
News & Media
Once the programs are run and the results sent back to the Trust, an "InChI Certified" logo is sent to the appropriate person or organization.
Science
I certified Martha Stewart's yard as a National Wildlife Federation Certified Wildlife Habitatt".
News & Media
During dinner I certified the beautiful ladies one by one to the tune of great applause and many tears from us all.
News & Media
Sample language could include, "I hereby certify that I have served a copy of this document on [insert name of other party] either by person or by mailing it postage prepaid on [insert the date]."[6].
Wiki
Expert writing Tips
Best practice
When using "I certify" in formal documents, clearly specify what you are certifying and the scope of your certification to avoid ambiguity. Example: "I certify that this review is based on my own experience."
Common error
Avoid using "I certify" in casual conversations or informal writing. It sounds overly formal and can be replaced with simpler phrases like "I confirm" or "I can assure you" for a more natural tone.
Linguistic Context
The phrase "I certify" serves as a performative utterance, where the act of saying it constitutes the act of certifying. According to Ludwig, this phrase is used to formally declare the truth or validity of a statement or document. It often appears in contexts requiring a formal assurance.
Frequent in
News & Media
32%
Science
29%
Wiki
18%
Less common in
Formal & Business
14%
Reference
5%
Social Media
2%
Ludwig's WRAP-UP
In summary, the phrase "I certify" is a formal declaration used to affirm the truth or accuracy of something. Ludwig's analysis reveals that this phrase is commonly used in News & Media, Science, and Wiki contexts, highlighting its versatility across different fields. While grammatically correct and widely accepted, it's important to reserve it for formal situations where a strong assurance is required. Alternatives like "I attest" or "I declare" can be used for similar effect, but "I certify" carries a unique weight of authority. Based on Ludwig AI insights, remember to be specific in your certification and avoid overuse in informal settings.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
I attest
Replaces "certify" with a synonym emphasizing the declaration of truth.
I confirm
Simple and direct replacement for "certify", indicating agreement with a statement.
I warrant
Substitutes "certify" with a term implying a guarantee or assurance.
I verify
Focuses on confirming the accuracy or truth of something.
I declare
Replaces "certify" with a more general term for making a formal statement.
I affirm
Similar to "declare", but carries a stronger sense of conviction.
I vouch for
Implies personal endorsement or support for the accuracy of something.
I guarantee
Indicates a strong assurance of the truth or quality of something.
I give assurance
Offers a formal assurance regarding the accuracy or validity of information.
I give my word
Highlights the personal commitment to the truthfulness of the statement.
FAQs
How to use "I certify" in a sentence?
Use "I certify" to formally declare the truth or accuracy of something. For example, "I certify that the information provided is accurate" or "I certify this to be a true likeness of the applicant".
What can I say instead of "I certify"?
When is it appropriate to use "I certify"?
It's best to use "I certify" in formal settings such as legal documents, official statements, or academic papers. It adds a level of formality and seriousness to your declaration.
Which is correct, "I certify" or "I certified"?
"I certify" is used to make a current declaration. "I certified" is used to refer to a past action. For example: "I certify that the document is correct" versus "I certified the document yesterday".
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