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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 require
Grammar usage guide and real-world examplesUSAGE SUMMARY
"which require" is correct and usable in written English.
You can use it when discussing a specific task or set of conditions. For example, "Getting the job done involved a set of tasks which require skill and patience."
✓ Grammatically correct
News & Media
Science
Academia
Formal & Business
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
Economic activities which require approval.
Academia
"Air pollution leads to chronic diseases which require hospital space.
News & Media
It penalizes rooms with high ceilings, which require more lighting.
News & Media
But sometimes boycotts, which require organization and consumer awareness, fail.
News & Media
The reality is unprecedented economic times, which require unprecedented responses".
News & Media
Authentication failures are only tracked for principals which require preauthentication.
Issues which require further research are also discussed.
Points of detail which require further study are elucidated.
Those sites, some of which require a fee, make business sense.
News & Media
And services, which require less energy than manufacturing, became a far bigger share of the economy.
News & Media
There are theme-park-style rides in Nicco Park too, which require a separate ticket.
News & Media
Expert writing Tips
Best practice
When using "which require", ensure the clause it introduces is nonrestrictive and provides additional, non-essential information. Use commas to set off the clause.
Common error
Avoid using "which" in restrictive clauses. If the information is essential to the sentence's meaning, use "that" instead of "which". For example, use "the tasks that require skill" instead of "the tasks which require skill" if the type of tasks is essential information.
Source & Trust
88%
Authority and reliability
4.6/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "which require" functions as a relative clause, specifically a nonrestrictive (or non-defining) relative clause. It adds extra information to a noun or noun phrase without being essential to its meaning. Ludwig provides numerous examples showing its use in various contexts.
Frequent in
News & Media
35%
Science
25%
Academia
15%
Less common in
Formal & Business
10%
Wiki
5%
Reference
0%
Ludwig's WRAP-UP
In summary, "which require" is a grammatically sound and frequently employed phrase used to introduce nonrestrictive clauses, adding supplemental information to a preceding noun. Ludwig AI confirms its correctness and provides a wide array of examples showcasing its use across diverse contexts, particularly in News & Media and Science. When utilizing "which require", remember to use commas to offset the clause and differentiate it from essential information clauses, which use "that" instead. Using alternative phrases such as "that necessitate" can add nuance to your writing.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
that necessitate
Emphasizes a stronger sense of need or inevitability.
that demand
Highlights the imperative or urgent nature of the requirement.
that call for
Implies a request or suggestion, making it slightly less forceful.
that necessitate the need for
Adds redundancy for emphasis on requirement.
that make necessary
Rephrases the requirement using a different grammatical structure.
that involve
Indicates inclusion, suggesting the requirement is part of a larger process.
that depend on
Highlights the dependence of something on specific conditions.
that are contingent on
Emphasizes the conditional aspect of the requirement.
that stipulate
Indicates a formal or legal requirement.
that prescribe
Suggests a rule or guideline that must be followed.
FAQs
How can I use "which require" in a sentence?
Use "which require" to introduce a nonrestrictive clause that provides additional information about the noun it modifies. For example, "The project, which require significant funding, is currently on hold."
What are some alternatives to "which require"?
You can use alternatives such as "that necessitate", "that demand", or "that call for" depending on the context.
Is it better to use "which require" or "that require"?
"Which require" introduces nonrestrictive clauses (additional, non-essential information), while "that require" introduces restrictive clauses (essential information). Choose based on whether the clause is essential to the sentence's meaning.
What's the difference between "which require" and "which requires"?
"Which require" is used when referring to a plural noun or concept, while "which requires" is used for singular nouns. For example, "The tasks which require attention" vs "The task which requires attention."
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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
88%
Authority and reliability
4.6/5
Expert rating
Real-world application tested