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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
in when to use
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "in when to use" is not correct and not usable in written English. It seems to be an incomplete expression and lacks clarity. An example could be: "I am unsure in when to use this term." Alternative expressions could be "when to apply," "when to utilize," or "when to employ."
⚠ May contain grammatical issues
News & Media
Science
Wiki
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
3 human-written examples
"I wish they'd take that nigger's picture off," the soldier said, a moment before Browne granted him "a lesson in when to use that word and when you should not use that word - a physical lesson".
News & Media
In his nearly six years running the department, which had a reputation for overly aggressive, and sometimes deadly, policing, Brown has proved to be a reformer, firing rogue cops for poor behavior, and making sure all officers got extra training in when to use lethal force.
News & Media
Police, she said, need to be trained thoroughly in when to use lethal force.
News & Media
Human-verified similar examples from authoritative sources
Similar Expressions
57 human-written examples
Physicians in this country have a free hand in deciding when to use new technology like CT angiography.
News & Media
The trick is in knowing when to use the press and when to avoid it.
News & Media
By tying military action to additional revenue, the president would have a freer hand in deciding when to use force.
News & Media
By tying military action to additional revenue, the president would actually have a freer hand in deciding when to use force.
News & Media
In addition, these patients may have a knowledge deficit in how and when to use their medications.
There's a lot more caution in terms of when to use them.
News & Media
In essence these are "when?" (to use them), "what?" (to include) and "how?" (to display them).
Science
In contrast, people choose when to use contraceptives, a low-cost product, turning premiums into advance payment for routine services.
News & Media
Expert writing Tips
Best practice
Avoid using the phrase "in when to use" in formal writing. Opt for grammatically correct alternatives such as "when to use" or "when to apply" for clarity and precision.
Common error
A common mistake is to add unnecessary prepositions like "in" before "when" in phrases. This can create grammatically incorrect sentences. Ensure that "when to use" is not preceded by extra prepositions to maintain clarity.
Source & Trust
77%
Authority and reliability
2.8/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "in when to use" is grammatically incorrect and does not serve a standard function in English. Ludwig AI identifies the phrase as flawed, suggesting it's an incomplete expression needing correction. It appears as an attempt to combine a preposition with a relative clause, resulting in ungrammatical construction.
Frequent in
News & Media
33%
Science
33%
Wiki
33%
Less common in
Academia
0%
Formal & Business
0%
Reference
0%
Ludwig's WRAP-UP
In summary, the phrase "in when to use" is grammatically incorrect and should be avoided in both formal and informal writing. As Ludwig AI suggests, it's better to use alternatives like "when to use", "when to apply", or "when to utilize" to maintain clarity and correctness. The sources where the phrase appears are varied, but its infrequent and incorrect usage suggests that writers should opt for more standard English phrasing. While this is present in some news media, wiki and science source, it is still not advisable to use the phrase.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
appropriate time to use
Focuses on the suitability of a particular time for usage.
when to apply
Offers a more concise and grammatically sound way of expressing the timing of an application.
best time to utilize
Specifies the optimal timing for utilization.
when to utilize
Replaces "in when to use" with a clearer and grammatically correct phrase using "utilize" instead of "use".
when to employ
Similar to "utilize", but "employ" may be more suitable in certain formal contexts.
circumstances for using
Shifts the focus to the circumstances that dictate usage.
proper occasion to apply
Emphasizes the correctness and appropriateness of the occasion.
situations for application
Highlights specific situations where something should be applied.
under what conditions to use
Focuses on the specific conditions that warrant usage.
in which instances to apply
Highlights specific instances where application is appropriate.
FAQs
What's grammatically correct, "in when to use" or "when to use"?
"When to use" is grammatically correct. The inclusion of "in" before "when" is unnecessary and creates an incorrect phrase.
How can I rephrase "in when to use" to be more clear?
You can use alternatives such as "when to apply", "when to utilize", or "the appropriate time to use" depending on the context.
Is "in when to use" ever appropriate in formal writing?
No, "in when to use" is generally not appropriate for formal writing due to its grammatical incorrectness. Always choose a clearer and more grammatically sound alternative.
What's the difference between "in when to use" and "at when to use"?
Both "in when to use" and "at when to use" are grammatically incorrect. The correct way to phrase it is simply "when to use" without the additional preposition.
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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
77%
Authority and reliability
2.8/5
Expert rating
Real-world application tested