I definitely know

USAGE SUMMARY

The phrase "I definitely know" is correct and usable in written English.
You can use it to express certainty or confidence about a piece of information or a fact. Example: "I definitely know that the meeting is scheduled for 10 AM tomorrow."

✓ Grammatically correct

News & Media

Human-verified examples from authoritative sources

Exact Expressions

53 human-written examples

"I definitely know how fortunate I am".

The New York Times - Sports

I definitely know what he's going through.

The New York Times - Sports

"I definitely know that I want children.

The Guardian - Business

I definitely know when it's not a good place.

The New York Times - Arts

I definitely know how to talk to people now".

The New York Times

"Actually, I don't know why I'm being modest; I definitely know every starting player".

The New York Times

Tommy Davis told me, "I definitely know where she is," but he won't disclose where that is.

The New Yorker

I am very calm and relaxed, because I definitely know that I did no such thing.

The Guardian - Sport

And one final thing I definitely know — work with people you like, trust and believe in.

The Guardian

I definitely know I could run a lot faster over that distance".

The New York Times

I definitely know how tricky it is, considering how the ball comes of the wall.

The New York Times - Sports

Expert writing Tips

Best practice

Use "I definitely know" when you want to express a strong sense of certainty and confidence in your knowledge. Avoid overuse in formal writing; consider more nuanced alternatives like "I am certain".

Common error

Avoid using "I definitely know" when you are actually making an assumption or inference. Use phrases like "I believe" or "I suspect" when you lack concrete evidence.

Linguistic Context

The phrase "I definitely know" functions as an assertive statement, expressing the speaker's strong conviction or certainty regarding a particular piece of information. It is a declaration of assured knowledge, as supported by Ludwig's examples.

Expression frequency: Very common

Frequent in

News & Media

86%

Formal & Business

7%

Science

7%

Less common in

Encyclopedias

0%

Wiki

0%

Reference

0%

Ludwig's WRAP-UP

In summary, "I definitely know" is a common and grammatically correct phrase used to express strong certainty. Ludwig AI confirms its validity and widespread use, particularly in news and media contexts. While suitable for various situations, it's important to be mindful of the level of formality required and to avoid overstating one's knowledge. Consider alternatives like "I am certain" or "I know for sure" for more formal settings or nuanced expressions of knowledge. Remember to avoid using it if the knowledge is based on assumption.

More alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

I know for sure

Adds "for sure" to emphasize the certainty of the knowledge.

I'm positive

Expresses a confident and unwavering belief.

I am certain

Replaces "definitely know" with a more formal expression of certainty.

I am sure

Similar to "I am certain", offering a slightly less formal alternative.

I am convinced

Indicates a strong belief based on evidence or reasoning.

Without a doubt, I know

Emphasizes the absence of any uncertainty in one's knowledge.

I have no doubt

Expresses certainty by negating any doubt about the information.

I can confirm

Offers assurance or verification of a fact or statement.

I'm fully aware

Emphasizes complete awareness and understanding of a situation.

It's my understanding

States knowledge based on information received or gathered.

FAQs

How can I use "I definitely know" in a sentence?

You can use "I definitely know" to express certainty about something. For example, "I definitely know that the meeting is scheduled for tomorrow."

What are some alternatives to "I definitely know"?

Depending on the context, you can use alternatives like "I am certain", "I know for sure", or "I have no doubt".

Is "I definitely know" appropriate for formal writing?

While grammatically correct, "I definitely know" might be too informal for certain formal contexts. Consider using more sophisticated alternatives like "I am certain" or "I can confirm".

What is the difference between "I definitely know" and "I think I know"?

"I definitely know" expresses certainty, while "I think I know" suggests uncertainty or a possibility of being incorrect. The former is a statement of confidence, while the latter implies a degree of doubt.