could not ascertain

USAGE SUMMARY

The phrase "could not ascertain" is correct and usable in written English.
It can be used when expressing an inability to determine or find out information or facts. Example: "After reviewing the evidence, we could not ascertain the cause of the malfunction."

✓ Grammatically correct

News & Media

Science

Human-verified examples from authoritative sources

Exact Expressions

60 human-written examples

Its investigation found Cho used abusive language to flight attendants but could not ascertain if she used violence.

The Guardian

He said he could not ascertain how the government was coming to its official count, or where the count was taking place.

The New York Times

Justice Erlbaum said, however, that he could not ascertain beyond a reasonable doubt that what had happened in Mr. Monserrate's apartment had been an intentional attack.

The New York Times

Campaign officials said yesterday that they could not ascertain whether the seven donations last spring were funneled from people other than the stated donors.

The New York Times

In Doha last night al-Jazeera's chairman, Hamad bin Thamer, said the channel "could not ascertain" if its Baghdad bureau had been targeted by the US.

The Guardian

Second, you'd need to be in a position where you possess critical, objective knowledge about the applicant that a third party could not ascertain.

The New York Times - Magazine

His friends in this State could not ascertain his whereabouts till September last, when they received a letter from him advising them that he was held in slavery, and asking their interposition to secure his release.

The Guardian

Her doctors could not ascertain, but it left my mother dizzy, weak and confused.

Forbes

Using monthly data, we found a good correlation between CAPE and rainfall; however, we could not ascertain the trend.

Earth, Planets and Space

Further, as the sample was modest, we could not ascertain which medications (as monotherapies or combinations) were more effective in combination with aripiprazole.

International Journal of Bipolar Disorders

However, the experiments could not ascertain if a user would have given the same importance to the chair's historical identity over comfort.

Chinese Journal of Mechanical Engineering

Expert writing Tips

Best practice

When using "could not ascertain", ensure the context clearly indicates what information you were unable to determine and why. This adds clarity and strengthens your statement.

Common error

While grammatically correct, "could not ascertain" can sound overly formal in casual writing or conversation. Opt for simpler alternatives like "couldn't find out" or "didn't know" to maintain a natural tone.

Linguistic Context

The phrase "could not ascertain" functions as a declarative statement expressing an inability to determine or establish something definitively. This is supported by Ludwig AI's analysis of numerous examples where the phrase is used to convey a lack of certainty or conclusive evidence.

Expression frequency: Very common

Frequent in

Science

45%

News & Media

44%

Wiki

3%

Less common in

Formal & Business

1%

Encyclopedias

0%

Reference

0%

Ludwig's WRAP-UP

In summary, the phrase "could not ascertain" is a grammatically correct and frequently used expression indicating an inability to determine or establish something with certainty. As Ludwig AI confirms, it is versatile and appears in a wide range of contexts, with a strong presence in science and news media. While useful in professional and formal settings, consider using simpler alternatives in informal conversation. Be clear about what you were unable to determine to enhance clarity. Top sources like the New York Times and scientific journals demonstrate its usage in authoritative contexts.

More alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

could not determine

Replaces "ascertain" with "determine", a direct synonym, maintaining a similar level of formality.

unable to ascertain

Uses "unable" instead of "could not", offering a more formal tone while retaining the core meaning.

were unable to determine

Combines "were unable" with "determine", providing a slightly more verbose alternative.

could not establish

Substitutes "ascertain" with "establish", emphasizing a failure to firmly prove or demonstrate something.

could not confirm

Replaces "ascertain" with "confirm", highlighting the inability to verify or validate information.

failed to ascertain

Emphasizes the failure aspect more strongly than the original phrase.

it was not possible to ascertain

Offers a more passive and indirect way of expressing the inability to ascertain.

lacked the ability to ascertain

Highlights the absence of the capacity or means to ascertain something.

the facts could not be ascertained

Shifts the focus to the facts themselves, emphasizing that they resisted being ascertained.

remained uncertain about

Emphasizes the state of uncertainty resulting from the inability to ascertain.

FAQs

What does "could not ascertain" mean?

The phrase "could not ascertain" means that someone was unable to find something out for certain or determine it through investigation or analysis.

How can I use "could not ascertain" in a sentence?

Use "could not ascertain" to indicate an inability to determine a fact or piece of information after inquiry or examination. For example: "The investigators "could not ascertain" the cause of the fire."

What can I say instead of "could not ascertain"?

You can use alternatives like "could not determine", "unable to ascertain", or "failed to ascertain" depending on the context.

Is "could not ascertain" formal?

Yes, "could not ascertain" is considered a formal phrase. In informal contexts, consider using simpler alternatives like "couldn't find out" or "didn't know".