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Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
completely sure
Grammar usage guide and real-world examplesUSAGE SUMMARY
"completely sure" is a correct and usable phrase in written English.
It can be used to emphasize the degree of certainty in a situation. For example: "I'm completely sure I can finish the project before the deadline."
✓ Grammatically correct
News & Media
Academia
Wiki
Alternative expressions(20)
absolutely certain
entirely convinced
without a doubt
quite sure
absolutely positive
definitely certain
utterly confident
absolutely sure
completely comfortable
perfectly sure
entirely sure
completely confident
exactly sure
totally sure
utterly sure
completely secure
completely convinced
unquestioningly certain
any doubts whatsoever
without any reservation
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
DJ MikeQ: I mean, I'm not completely sure.
News & Media
"I'm completely sure".
News & Media
I'm not completely sure why.
News & Media
I'm not completely sure what happened, though".
News & Media
Doctors aren't completely sure why melanoma rates are soaring.
Academia
I'm not completely sure where I am now".
News & Media
"I'm completely sure most people support it," he said.
News & Media
I thought I saw him, but I'm not completely sure.
News & Media
But Ford itself never seemed completely sure of the concept.
News & Media
"But they all looked completely sure about their power.
News & Media
They were both completely sure of what they looked like".
News & Media
Expert writing Tips
Best practice
Use "completely sure" when you want to strongly emphasize your certainty about something. It adds more weight than simply saying "sure".
Common error
Avoid using "completely sure" in every sentence where you express certainty. Vary your language with synonyms like "absolutely certain" or "entirely convinced" to maintain reader engagement.
Source & Trust
80%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "completely sure" functions as an adjectival phrase that modifies a subject. It is used to express a strong degree of certainty or conviction. Ludwig provides numerous examples of its usage in various contexts, indicating its widespread applicability.
Frequent in
News & Media
35%
Academia
25%
Wiki
20%
Less common in
Science
10%
Formal & Business
5%
Reference
5%
Ludwig's WRAP-UP
In summary, "completely sure" is a versatile adjectival phrase used to express a strong sense of certainty across a variety of contexts. As Ludwig AI confirms, it is grammatically correct and widely used, particularly in News & Media, Academia, and Wiki sources. While highly effective for conveying conviction, it's important to vary your language with alternatives like "absolutely certain" or "entirely convinced" to avoid overuse. Mastering the proper usage of "completely sure" and its synonyms will enhance the clarity and impact of your writing.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
absolutely certain
Replaces "sure" with "certain" and "completely" with "absolutely", emphasizing a strong degree of conviction.
absolutely positive
Replaces "sure" with "positive" and "completely" with "absolutely", reinforcing a firm belief.
definitely certain
Adds "definitely" for emphasis, reinforcing the certainty of the statement.
without a doubt
Expresses certainty by negating the possibility of doubt, indicating unwavering conviction.
entirely convinced
Shifts from "sure" to "convinced", focusing on the internal state of belief rather than outward assurance.
beyond any question
Similar to "without a doubt", this phrase asserts that there is no room for uncertainty.
utterly confident
Uses "confident" instead of "sure", highlighting a feeling of self-assurance in one's belief.
unquestionably sure
Implies that the sureness is so evident that it cannot be questioned.
fully persuaded
Emphasizes the process of becoming convinced, implying a thorough evaluation of evidence.
positive without reservation
Highlights the absence of any hesitation or qualification in one's certainty.
FAQs
What does "completely sure" mean?
The phrase "completely sure" means you are entirely certain about something, leaving no room for doubt. It's a stronger way of saying you are "sure".
How can I use "completely sure" in a sentence?
You can use "completely sure" to express strong conviction. For example: "I am completely sure I locked the door" or "She seemed completely sure of her answer".
What are some alternatives to "completely sure"?
You can use alternatives like "absolutely certain", "entirely convinced", or "without a doubt" depending on the context.
Is there a difference between "completely sure" and "quite sure"?
"Completely sure" implies a higher degree of certainty than "quite sure". While "quite sure" suggests a reasonable level of confidence, "completely sure" leaves no room for doubt.
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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
80%
Authority and reliability
4.5/5
Expert rating
Real-world application tested