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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
once they are
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "once they are" is correct and usable in written English.
It can be used to indicate a condition or situation that occurs after a certain point in time or after a specific action has been completed. Example: "Once they are finished with their tasks, they can take a break."
✓ Grammatically correct
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
60 human-written examples
And another 10 once they are served.
News & Media
Once they are translucent, add the stock.
News & Media
Once they are well established, that's it.
News & Media
For once, they are entirely justified.
News & Media
Once they are accepted, most revert to their actual names.
News & Media
Once they are in power, they forget the people".
News & Media
Once they are gone, Tracy starts cleaning up.
News & Media
Once they are over I forget about them.
News & Media
Once they are in place, prices can no longer rise.
News & Media
Once they are in a different brand, they're gone.
News & Media
And all at once, they are at six points apiece.
News & Media
Expert writing Tips
Best practice
Use "once they are" to clearly establish a sequence of events, making sure the timing of actions is unambiguous. For instance, "Once they are approved, the funds will be released."
Common error
Avoid using "once they is" when referring to a plural subject. Remember that "they" is plural, so the correct form is always "once they are".
Source & Trust
79%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "once they are" functions as an adverbial clause of time, introducing a condition that must be met before the main clause can occur. As Ludwig AI confirms, it's a common and acceptable way to structure sentences indicating sequential events.
Frequent in
Wiki
39%
News & Media
37%
Science
24%
Less common in
Formal & Business
0%
Academia
0%
Encyclopedias
0%
Ludwig's WRAP-UP
In summary, the phrase "once they are" functions as an adverbial clause of time, clearly indicating that an action will occur after a specific condition is met. Ludwig AI confirms it's grammatically sound and prevalent in various contexts, particularly in News & Media, Science and Wiki. While generally neutral in tone, consider more formal alternatives like "after they have been" in scientific or academic writing. Ludwig’s analysis underscores the importance of correct subject-verb agreement, reminding writers to avoid errors like "once they is". By adhering to best practices and understanding the nuances of its usage, you can confidently incorporate "once they are" into your writing to establish clear temporal relationships.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
as soon as they are
Emphasizes the immediacy of the subsequent action.
after they have been
Focuses on the completion of an action prior to the subsequent state.
when they become
Highlights the transition into a new state or condition.
after they get
A more informal alternative.
subsequent to them being
A more formal phrasing emphasizing the sequence of events.
following their
More concise, often used when referring to a specific event or action.
upon their
A more formal and immediate sequence.
post their
A shortened, somewhat informal way to indicate 'after'.
on the condition that they are
Adds a conditional element to the sequence.
provided that they are
Similar to 'on the condition that', but slightly less formal.
FAQs
How can I use "once they are" in a sentence?
The phrase "once they are" introduces a dependent clause indicating when something will happen. For example: "Once they are finished, we can leave."
What can I say instead of "once they are"?
Alternatives include "after they are", "when they are", or "as soon as they are" depending on the context.
Is it correct to say "once they is" instead of "once they are"?
No, "once they is" is grammatically incorrect. The correct form is "once they are" because "they" is a plural pronoun and requires the plural form of the verb "to be".
What's the difference between "once they are" and "if they are"?
"Once they are" implies a sequence where something happens after a condition is met. "If they are" sets a condition without necessarily implying a sequence. For example, "Once they are ready, we'll begin" suggests a start time. "If they are ready, we might begin" expresses uncertainty.
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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
79%
Authority and reliability
4.5/5
Expert rating
Real-world application tested