Used and loved by millions
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
could not identify
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "could not identify" is correct and usable in written English.
You can use it when expressing an inability to recognize or determine something or someone. Example: "After reviewing the evidence, the detective could not identify the suspect in the lineup."
✓ Grammatically correct
News & Media
Science
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
Her father could not identify the body.
News & Media
He could not identify the component.
News & Media
X. returned they could not identify him.
News & Media
But he could not identify Mr. Schwarz.
News & Media
Ms. Barrett could not identify her attacker.
News & Media
I could not identify with him".
News & Media
Ms. Glover could not identify her attackers.
News & Media
A police spokesman said he could not identify the medication.
News & Media
Club officers could not identify who painted William Taft.
News & Media
She could not identify the type of rifle.
News & Media
Another witness, however, could not identify the man.
News & Media
Expert writing Tips
Best practice
Consider the level of formality required; while "could not identify" is generally acceptable, more formal situations might benefit from alternatives like "was unable to identify".
Common error
Avoid using "could not identify" when a more specific verb better describes the situation. For instance, if the problem is understanding something, use "could not understand" instead of a general "could not identify".
Source & Trust
89%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "could not identify" functions as a negative verb phrase, expressing an inability or failure to recognize or determine something. Ludwig AI confirms its correctness and usability. The phrase combines the modal verb 'could', the negation 'not', and the verb 'identify'.
Frequent in
News & Media
40%
Science
35%
Formal & Business
10%
Less common in
Encyclopedias
5%
Wiki
5%
Reference
5%
Ludwig's WRAP-UP
The phrase "could not identify" is a versatile and grammatically sound expression used to indicate an inability to recognize or determine something. Ludwig AI attests to its correctness. It's most prevalent in news and scientific contexts, reflecting its utility in objective reporting and analysis. While generally neutral in tone, alternatives like "was unable to identify" can add formality. When crafting your writing, ensure clarity in specifying what couldn't be identified and avoid overuse by considering more specific verbs when applicable. With 65 real-world examples, the phrase is considered very common. Top authoritative sources include The New York Times, The Guardian and The New Yorker.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
was unable to identify
Replaces "could" with "was able", maintaining a formal tone and similar meaning.
could not recognize
Substitutes "identify" with "recognize", focusing on the act of knowing something again.
failed to identify
Uses "failed" to emphasize a lack of success in identifying something.
was incapable of identifying
Emphasizes a lack of capability, suggesting a stronger inability.
could not determine
Replaces "identify" with "determine", shifting the focus to ascertaining something.
remained unable to identify
Indicates a persistent inability to identify something over time.
could not discern
Uses "discern" to suggest a difficulty in perceiving or distinguishing something.
lacked the ability to identify
Highlights the absence of the skill or power to identify.
could not pinpoint
Replaces "identify" with "pinpoint", focusing on locating something precisely.
were unable to ascertain
A more formal alternative, using "ascertain" to mean finding something out for certain.
FAQs
What can I say instead of "could not identify"?
You can use alternatives like "was unable to identify", "failed to identify", or "could not recognize" depending on the context.
Is "could not identify" grammatically correct?
Yes, "could not identify" is grammatically correct. It follows standard English grammar rules for expressing an inability to recognize or determine something.
How do I use "could not identify" in a sentence?
Use "could not identify" to indicate a failure to recognize or determine something. For example: "The witness "could not identify" the suspect in the lineup".
What's the difference between "could not identify" and "could not recognize"?
While similar, ""could not identify"" generally implies a failure to determine something's specific nature or source, while "could not recognize" focuses on a failure to remember or know something from a previous encounter.
Editing plus AI, all in one place.
Stop switching between tools. Your AI writing partner for everything—polishing proposals, crafting emails, finding the right tone.
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
4.5/5
Expert rating
Real-world application tested