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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
primarily when it
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "primarily when it" is correct and usable in written English.
You can use it to indicate that something occurs mainly during a specific condition or situation. Example: "The system functions optimally primarily when it is connected to a stable internet source."
✓ Grammatically correct
Science
News & Media
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
2 human-written examples
GLUT1 protein is synthesised and degraded in the cytosol, whereas GLUT1 protein enacts its biological function primarily when it is transported to the cell membrane.
Science
The White House has gone into communications lock-down mode before, primarily when it is being heavily -- but legitimately -- criticized and it wants to punish the critics by ceasing all engagement with them for a period of time.
News & Media
Human-verified similar examples from authoritative sources
Similar Expressions
57 human-written examples
Otherwise, I considered gender presentation primarily when I was told to – this feedback gradually changed the way I dressed and behaved.
News & Media
A poor relation of the broccoli, the cabbage, and the brussels sprout, the kohlrabi is primarily noted (when it's noted at all) for its peculiar appearance.
News & Media
I mean, if I'm being honest, I barely remember it ever existing, primarily because when it was a big deal, I was seven or eight years old and more interested in catching fish and worrying about the weather than Bentley Rhythm Ace.
News & Media
The outline is as follows: we first note that the tetramer structure of PPDK makes possible an avidity effect, in which RP primarily acts when it is bound at the same time to two different monomers on the same tetramer.
Science
He saw philosophy as a source of insight and perspective relevant to politics, but after his early studies, devoted himself to it primarily when temporarily debarred from more active pursuits: one might say that philosophy became, beyond its intrinsic value, a form of alternative public service when the forum was too dangerous for him to enter (for further reflection, see Baraz 2012).
Science
The Black Panther Party was made up primarily by men when it was founded in 1966, but evolved into a female majority by the early 70s, according to Stanley Nelson Jr., director of The Black Panthers: Vanguard of the Revolution.
News & Media
Telemetry studies have shown that this species swims primarily at night, when it enters reefs and other habitats with high terrain relief, and spends most of the day in nearby open areas buried in sediment.
Wiki
In this study, cooling was observed primarily when water was turned on, not during the time it took the coat to dry.
Science
It was shown that heating and reaction occur primarily when particles pass through the plasma spout.
Science
Expert writing Tips
Best practice
Use "primarily when it" to clearly specify the main condition or situation in which an event or action predominantly occurs. This helps to avoid ambiguity and provides a precise context for the reader.
Common error
Avoid using "primarily when it" if the condition you are describing is not truly the main one. Ensure that the situation you are referencing is, in fact, the most common or significant context. If the event occurs under various conditions, a more general phrase might be more appropriate.
Source & Trust
81%
Authority and reliability
4.1/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "primarily when it" functions as an adverbial clause, modifying a verb or clause to indicate the main condition under which an action or event occurs. As Ludwig AI points out, it specifies the principal context while allowing for other possibilities.
Frequent in
Science
50%
News & Media
50%
Formal & Business
0%
Less common in
Encyclopedias
0%
Wiki
0%
Social Media
0%
Ludwig's WRAP-UP
In summary, the phrase "primarily when it" is a grammatically correct and useful construction to specify the main condition under which something occurs. According to Ludwig AI, it effectively conveys the principal context without excluding other possibilities. It is most commonly found in scientific and news-related articles, suitable for neutral to formal writing. When using this phrase, ensure that the condition you describe truly represents the most frequent or significant context to avoid overgeneralization.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
mainly when it
Replaces "primarily" with "mainly", indicating the principal but not exclusive condition.
chiefly when it
Substitutes "primarily" with "chiefly", emphasizing the main circumstance.
mostly when it
Uses "mostly" instead of "primarily" to suggest the majority of instances.
largely when it
Employs "largely" in place of "primarily", highlighting the significant condition.
especially when it
Replaces "primarily" with "especially", focusing on particular importance.
particularly when it
Uses "particularly" to emphasize a specific condition under which something occurs.
in most cases when it
Adds "in most cases" for broader implication of frequency.
for the most part when it
Employs "for the most part" to convey general conditionality.
predominantly when it
Substitutes "primarily" with "predominantly", indicating greater frequency.
typically when it
Uses "typically" to indicate a common occurrence under specific conditions.
FAQs
How can I use "primarily when it" in a sentence?
Use "primarily when it" to specify the main condition under which something happens. For example, "The software glitches "primarily when it" processes large files".
What are some alternatives to "primarily when it"?
You can use alternatives like "mainly when it", "especially when it", or "mostly when it" depending on the nuance you want to convey.
Is "primarily when it" formal or informal?
"Primarily when it" is suitable for both formal and informal contexts. The level of formality depends more on the surrounding vocabulary and the overall tone of the writing.
What's the difference between "primarily when it" and "only when it"?
"Primarily when it" indicates that something happens mostly under a specific condition, whereas "only when it" suggests that it exclusively happens under that condition.
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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
81%
Authority and reliability
4.1/5
Expert rating
Real-world application tested