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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
know how ought
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "know how ought" is not correct and does not make sense in written English.
It seems to be a confusion of terms and does not convey a clear meaning. Example: "I don't understand what you mean by 'know how ought' in this context."
⚠ May contain grammatical issues
Science
Encyclopedias
News & Media
Alternative expressions(2)
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
1 human-written examples
Stanley and Williamson argue, on broadly linguistic grounds, that our default view of know how ought to be rather different from Ryle's.
Science
Human-verified similar examples from authoritative sources
Similar Expressions
58 human-written examples
Precisely because Villehardouin did not know how histories "ought" to be written, however, his work lacked the conventional preface modestly declaring the author's lack of ability.
Encyclopedias
"The last thing you're going to hear from this podium is someone thinking they know how Afghanistan ought to organize itself," he said.
News & Media
I didn't know how I ought to take care of my children or my husband.
Science
They believe they know how the world ought to work".
News & Media
DESIGNERS are lofty idealists who know how the world ought to behave.
News & Media
Girls with feathers, vulgar songs – Washy verse on England's need – God – and don't we damned well know How the message ought to read.
News & Media
And on her BBC London radio show, Vanessa Feltz said: "We take seriously people feeling harassed or threatened or intimidated – of course I do, I've got two daughters … but I just don't know how seriously this ought to be taken".
News & Media
You want to know how a guy ought to dress?
News & Media
We know, or ought to know, how this story invariably ends.
News & Media
"If nothing else, one ought to know how to treat a comma".
News & Media
Expert writing Tips
Best practice
When expressing an expectation or obligation related to a skill, use the phrase "ought to know how" or "should know how" instead of the ungrammatical "know how ought".
Common error
Ensure that modal verbs like "ought" and "should" are followed by "to" when expressing obligation or advice related to an action. Using "know how ought" omits the necessary "to" and creates an ungrammatical sentence.
Source & Trust
86%
Authority and reliability
2.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "know how ought" attempts to express an expectation or obligation related to possessing a skill or knowledge. However, it is grammatically incorrect. Ludwig AI confirms this assessment. It lacks the necessary "to" between "ought" and "know", resulting in an ungrammatical structure.
Frequent in
News & Media
30%
Science
30%
Encyclopedias
20%
Less common in
Formal & Business
10%
Wiki
5%
Reference
5%
Ludwig's WRAP-UP
In summary, the phrase "know how ought" is grammatically incorrect and should be avoided. As Ludwig AI points out, it lacks the necessary "to" between "ought" and "know". To properly convey the intended meaning of expectation or obligation related to a skill, use "ought to know how" or "should know how" instead. While the phrase might appear in various sources, its infrequency and grammatical incorrectness make it unsuitable for formal writing.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
ought to know how
Uses the full "ought to" construction, making the phrase grammatically correct and conveying a sense of duty or expectation.
should know how
Replaces "ought" with "should", indicating a recommendation or expectation of knowing how to do something.
know how to
Focuses on the ability to do something, removing the sense of obligation or expectation.
understand how to
Emphasizes comprehension of the process rather than just the ability to perform it.
be expected to know how
Highlights the expectation that someone possesses a particular skill or knowledge.
need to know how
Indicates a requirement or necessity to acquire a specific skill or knowledge.
have to know how
Expresses an obligation or necessity to possess a particular skill or knowledge.
must know how
Conveys a strong obligation or requirement to possess a specific skill or knowledge.
are supposed to know how
Implies an assumption or expectation that someone possesses a particular skill or knowledge.
be required to know how
Indicates a formal requirement to possess a specific skill or knowledge.
FAQs
How can I correct the phrase "know how ought"?
The phrase "know how ought" is grammatically incorrect. You should use "ought to know how" or "should know how" instead.
What does "know how ought" mean?
The phrase "know how ought" doesn't have a standard meaning in English due to its incorrect grammatical structure. It likely intends to convey a sense of obligation or expectation regarding knowing how to do something, but it needs to be rephrased.
Is "know how ought" ever correct?
No, "know how ought" is not considered correct in standard English. The proper way to express this idea is by including the word "to": "ought to know how".
What are some alternatives to "know how ought"?
Alternatives include "should know how", "ought to know how", "need to know how", and "must know how", depending on the specific nuance you want to convey.
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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
86%
Authority and reliability
2.5/5
Expert rating
Real-world application tested