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Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
I sure that
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase 'I sure that' is not correct English.
To express certainty in English, you would need to use the phrase 'I am sure that'. For example: I am sure that the next day will be a beautiful day.
⚠ May contain grammatical issues
News & Media
Science
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
10 human-written examples
Am I sure that this is the right story?
News & Media
Was I sure that this man was my father?
News & Media
But nor am I sure that Desmond believed he was lying when he told me otherwise.
News & Media
Nor am I sure that Plath's work can be separated from her depression.
News & Media
Am I sure that he's not in the Russian Mafia, someone else asked.
News & Media
Valcke said: "Am I sure that 2018 and 2022 are free of any collusion?
News & Media
Human-verified similar examples from authoritative sources
Similar Expressions
50 human-written examples
I'm sure that's what I was doing.
News & Media
And I thought, Sure, that's what I love.
News & Media
"I'm sure that wasn't me," I said.
News & Media
"I'm sure that wasn't it".
News & Media
I'm sure that's true.
News & Media
Expert writing Tips
Best practice
When aiming for a formal tone, consider alternatives like "I am certain that" or "I am convinced that" instead of the more casual "I am sure that".
Common error
Ensure that the verb "to be" is included when expressing a state of being or certainty. Saying just "I sure that" is like saying "I happy" - it misses the necessary linking verb.
Source & Trust
89%
Authority and reliability
2.8/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "I sure that" is an incorrect attempt to express certainty or conviction. Correctly, it requires the auxiliary verb 'am' to form a complete sentence. As Ludwig AI states, the correct form should be 'I am sure that'.
Frequent in
News & Media
40%
Science
30%
Formal & Business
10%
Less common in
Academia
5%
Encyclopedias
5%
Wiki
10%
Ludwig's WRAP-UP
The phrase "I sure that" is grammatically incorrect, as it omits the necessary auxiliary verb "am". The proper way to express certainty is by saying "I am sure that". As Ludwig AI points out, without "am", the sentence fails to properly convey its intended meaning. While "I sure that" might appear in informal contexts, it is crucial to use the grammatically correct "I am sure that" in formal writing and professional communication. There are alternative ways to express confidence or belief, such as "I am certain that" or "I believe that", depending on the intended nuance.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
I am sure that
Addition of "am" corrects the grammar to express certainty.
I'm certain that
Replaces "sure" with "certain" for a more formal tone, while correcting the grammatical error.
I have no doubt that
Conveys strong certainty by negating doubt.
I am positive that
Substitutes "sure" with "positive" to convey a strong sense of conviction, while correcting the grammatical error.
I'm convinced that
Highlights a state of being persuaded or convinced.
I feel sure that
Emphasizes a feeling or intuition of certainty.
I believe that
Expresses a belief or opinion rather than absolute certainty.
I think that
Indicates a less firm belief or opinion.
It's my understanding that
Expresses certainty based on received information or comprehension.
I gather that
Suggests certainty based on indirect evidence or inference.
FAQs
What is the correct way to say "I sure that"?
The correct way to express certainty is to use the phrase "I am sure that". The auxiliary verb "am" is required for proper grammar.
What are some alternatives to "I am sure that"?
You can use alternatives like "I am certain that", "I am positive that", or "I believe that" depending on the context and the level of certainty you want to express.
Is "I sure that" ever acceptable in writing?
No, "I sure that" is generally not acceptable in formal or academic writing. It is considered grammatically incorrect. While it might appear in informal speech, it should be avoided in written communication. Always use "I am sure that" instead.
What's the difference between "I am sure that" and "I am certain that"?
While both phrases express certainty, "I am certain that" often implies a stronger level of conviction than "I am sure that". They can often be used interchangeably, but consider the nuance when choosing the most appropriate phrase.
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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
89%
Authority and reliability
2.8/5
Expert rating
Real-world application tested