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Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
i guarantee that
Grammar usage guide and real-world examplesUSAGE SUMMARY
"I guarantee that" is correct and usable in written English.
You can use it as a way of making a firm promise or assurance about something. For example: "I guarantee that I will be ready to leave by 5pm."
✓ Grammatically correct
News & Media
Sports
Opinion
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
I guarantee that will be more popular.
News & Media
"I guarantee that would probably make it easier to recruit".
News & Media
After one or two very public dismissals, I guarantee that trust, teamwork and confidentiality will prevail.
News & Media
Can I guarantee that?
News & Media
"I guarantee that will change," Tilden said.
News & Media
And I guarantee that is just the beginning.
News & Media
I guarantee that.
News & Media
I guarantee that you will love it.
News & Media
"I guarantee that there have been hundreds.
News & Media
I guarantee that there will be no shortage of applicants.
News & Media
"I guarantee that something major will be found," he says.
News & Media
Expert writing Tips
Best practice
Use "i guarantee that" to convey a strong sense of certainty and reliability when making a promise or assertion. Ensure that you are in a position to fulfill the guarantee.
Common error
While effective, overuse of "i guarantee that" can diminish its impact and make your writing sound repetitive. Vary your language by using alternatives like "i assure you" or "you can be sure".
Source & Trust
88%
Authority and reliability
4.6/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "i guarantee that" functions as an assertive speech act. It is used to express a strong conviction, promise, or assurance regarding a particular statement or future event. This is supported by Ludwig AI's analysis indicating the phrase is grammatically correct and widely used.
Frequent in
News & Media
40%
Sports
25%
Formal & Business
15%
Less common in
Science
10%
Wiki
5%
Reference
5%
Ludwig's WRAP-UP
In summary, "i guarantee that" is a grammatically sound and very common phrase used to express strong assurance or promise. As Ludwig AI confirms, it's widely accepted and employed across diverse contexts, especially in news, sports, and business settings. While effective, varying your language with synonyms like "i assure you that" or "i promise you that" can prevent overuse. Remember to use this phrase responsibly, ensuring you can fulfill the guarantee you are making to maintain credibility. The phrase has a neutral tonality and the communicative purpose is to instill confidence in the listener or reader.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
i assure you that
Replaces "guarantee" with "assure", offering a slightly more formal tone but conveying the same level of certainty.
i can assure you that
Adds "can" for a slightly less direct but equally confident statement.
i can promise you that
Substitutes "guarantee" with "promise", softening the tone while maintaining assurance.
i'm certain that
Expresses a high degree of confidence or conviction about something.
i can vouch for that
Offers a personal endorsement, implying strong belief in the truth or reliability of something.
you can be sure that
Shifts the focus to the listener's certainty, offering reassurance.
i'm convinced that
Indicates a strong belief based on evidence or reasoning.
without a doubt
Expresses certainty by negating any potential for doubt.
it is my firm belief that
Presents the statement as a deeply held conviction, emphasizing sincerity.
rest assured that
Offers a calming reassurance, suggesting that there's no need to worry.
FAQs
When is it appropriate to use "i guarantee that"?
Use "i guarantee that" when you want to express a firm commitment or assurance about a future outcome or present fact. It's suitable when you have a high degree of confidence in the accuracy or reliability of your statement.
What can I say instead of "i guarantee that"?
You can use alternatives like "i assure you that", "i promise you that", or "you can be sure that" depending on the context.
Is "i guarantee that" formal or informal?
"I guarantee that" is generally considered neutral in tone and can be used in both formal and informal settings, though it's important to consider your audience and context. For highly formal situations, "i assure you that" might be more appropriate.
What is the difference between "i guarantee that" and "i hope that"?
"I guarantee that" expresses certainty and a firm commitment, while "i hope that" expresses a desire or wish for something to happen without any assurance of it actually occurring. They convey opposite levels of confidence.
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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
4.6/5
Expert rating
Real-world application tested