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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
which occurs when
Grammar usage guide and real-world examplesUSAGE SUMMARY
"which occurs when" is correct and can be used in written English.
It is typically used to refer to something that happens at a specific point in time or as a result of a specific condition. For example: "Bullying is a serious problem, which occurs when a person is subjected to negative comments or behavior from another person."
✓ Grammatically correct
News & Media
Science
Academia
Encyclopedias
Wiki
Alternative expressions(5)
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
Human folly causes famine, which occurs when those ways are blocked.
News & Media
The first is the oligopolistic effect, which occurs when an agent can single-handedly influence prices.
Academia
Constraints may cause offset, which occurs when the set points are unreachable.
Science
It's the wealth effect, which occurs when rising asset prices make people feel more secure.
News & Media
One standard practice to prove a warrior's strength is the circumcision, which occurs when a male is in his teens.
News & Media
However, progress has been made, notably on stunting, which occurs when children are too short for their age.
News & Media
The most serious consequence is blindness, which occurs when the membrane behind the retina calcifies and develops cracks.
News & Media
Despite the intense pressure, no A&E unit had to close temporarily, which occurs when a hospital cannot cope.
News & Media
It recognizes that violence can be cultural, which occurs when beliefs are used to justify either direct or structural violence.
Encyclopedias
This one is related to the well-known quantum Zeno effect, which occurs when a quantum system is frequently measured.
News & Media
This is a natural state of paralysis, which occurs when elasmobranchs are positioned ventral side up in the water column.
News & Media
Expert writing Tips
Best practice
Use "which occurs when" to clearly define a condition or event that triggers a specific outcome. Ensure the clause following "when" accurately describes the triggering event.
Common error
Avoid embedding "which occurs when" within convoluted sentence structures. Aim for clarity by keeping the relationship between the event and its trigger direct and easy to understand. Break down complex sentences if necessary.
Source & Trust
84%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "which occurs when" functions as a relative clause introducing additional information about a noun or situation. Ludwig AI confirms the correctness and utility of this phrase. It commonly clarifies the conditions or circumstances under which something happens.
Frequent in
News & Media
39%
Science
32%
Academia
11%
Less common in
Encyclopedias
7%
Wiki
6%
Formal & Business
5%
Ludwig's WRAP-UP
In summary, "which occurs when" is a versatile phrase used to specify the conditions or timing of an event. Ludwig AI indicates that it's grammatically sound and widely applicable across various contexts. As highlighted by Ludwig's examples, this phrase appears frequently in news, science, and academic writing, making it suitable for formal and neutral registers. To maintain clarity, avoid embedding it within overly complex sentence structures. Consider alternatives like "that happens when" or "that arises when" for slight variations in meaning or tone. Ultimately, mastering the use of "which occurs when" allows for precise and informative communication.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
that happens when
Replaces "occurs" with the more informal "happens", maintaining the same meaning.
that arises when
Substitutes "occurs" with "arises", indicating the beginning or emergence of something.
that results when
Replaces "occurs" with "results", focusing on the outcome of a specific condition.
that takes place when
Replaces "occurs" with "takes place", emphasizing the event or action happening.
that is triggered when
Uses "triggered" to highlight the initiating event or condition.
that is present when
Focuses on the state of being during a specific time or condition.
that is observed when
Highlights the act of noticing or witnessing something under specific conditions.
that is evident when
Emphasizes the clarity or obviousness of something under certain conditions.
that is manifested when
Uses "manifested" to describe the way something appears or becomes apparent.
that comes about when
Substitutes "occurs" with "comes about", indicating how something begins to exist or happen.
FAQs
How can I use "which occurs when" in a sentence?
Use "which occurs when" to define or explain the circumstances under which something happens. For example: "Coral bleaching, "which occurs when" seawater becomes even slightly warmer than average highs, is a major threat to reefs."
What are some alternatives to "which occurs when"?
Alternatives include phrases like "that happens when", "that arises when", or "that results when", depending on the specific nuance you want to convey. Consider "that happens when" for a more informal tone.
Is it better to use "that occurs when" instead of "which occurs when"?
In most cases, "which" is preferred when introducing non-restrictive clauses that provide additional information, whereas "that" is used for restrictive clauses essential to the sentence's meaning. Thus, "which occurs when" is generally more appropriate when providing extra context.
How does the formality of "which occurs when" compare to other similar phrases?
The phrase "which occurs when" is generally considered neutral to formal in tone, suitable for academic, news, and professional writing. Phrases like "that happens when" are more informal.
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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
84%
Authority and reliability
4.5/5
Expert rating
Real-world application tested