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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
primary source
Grammar usage guide and real-world examplesUSAGE SUMMARY
"primary source" is an appropriate and usable part of a sentence in written English.
You can use it to refer to a document or other piece of evidence that provides first-hand information about a subject. For example, "The primary source for this research is a collection of eyewitness accounts from the early 1900s."
✓ Grammatically correct
News & Media
Science
Encyclopedias
Alternative expressions(20)
original source
firsthand account
initial source
original document
direct evidence
mainspring
key foundation
key source
a go-to resource
basic source
fundamental source
predominant source
indispensable asset
foundational source
point of reference
trusted authority
reliable source
first port of call
main source
mainstay
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
59 human-written examples
(See primary source document: Inaugural Address).
Encyclopedias
Goya was an obvious, primary source.
News & Media
Hip-hop is a primary source of this new music.
News & Media
The primary source was the imprisoned dictator himself.
News & Media
Was that structure informed by the primary source material?
News & Media
And our primary source, at present, is fossil fuel.
News & Media
What is the primary source of mercury pollution?
News & Media
(McBurney's primary source is Petru Popescu's nonfiction account, Amazon Beaming).
News & Media
The fee is Digital Convergence's primary source of revenue.
News & Media
There are also primary source documents from WikiLeaks.
News & Media
Newspapers remain the primary source of news-gathering in America.
News & Media
Expert writing Tips
Best practice
When using "primary source" in academic writing, clearly identify the specific document or artifact you are referencing to enhance the credibility of your research.
Common error
Avoid relying solely on secondary sources when primary sources are available. Direct engagement with primary materials provides a more nuanced and informed understanding of the subject matter.
Source & Trust
82%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "primary source" functions as a noun phrase, typically serving as a subject, object, or complement within a sentence. As confirmed by Ludwig AI, it effectively conveys the idea of an original or foundational piece of evidence.
Frequent in
News & Media
33%
Science
32%
Encyclopedias
12%
Less common in
Formal & Business
3%
Wiki
3%
Reference
0%
Ludwig's WRAP-UP
In summary, "primary source" is a common noun phrase that indicates an original or foundational piece of evidence. Ludwig AI confirms its correct grammatical standing. As showcased by Ludwig's examples, its usage spans across diverse contexts, notably in news, scientific, and encyclopedic domains. To enhance your writing, clearly identify the specific document or artifact you're referencing. Alternatives include "original source" or "firsthand account", depending on your context. Remember to avoid over-reliance on secondary materials when
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
original source
Focuses on the authenticity and lack of alteration from its initial state.
firsthand account
Emphasizes direct personal experience or observation of an event.
initial source
Highlights the starting point or beginning of something.
original document
Specifically refers to a written record in its unaltered form.
direct evidence
Stresses the straightforward and unambiguous nature of the proof.
mainspring
Highlights the principal motive, cause, or influence.
chief source
Emphasizes the prominence and importance of the origin.
core ingredient
Highlights the fundamental component of something.
principal root
Focuses on the fundamental reason, cause, or beginning.
key foundation
Highlights the basis that supports or justifies something.
FAQs
How is a "primary source" different from a secondary source?
A "primary source" provides firsthand evidence about an event or topic, while a secondary source offers analysis or interpretation of primary sources.
What are some examples of "primary sources"?
Examples include diaries, letters, original manuscripts, photographs, and official documents. These provide direct insights without interpretation.
Where can I find reliable "primary sources" for research?
Libraries, archives, and online databases often host collections of "primary source" materials. Ensure the source is credible and properly cited.
What can I say instead of "primary source"?
Consider using alternatives like "original source", "firsthand account", or "initial source" depending on the context.
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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
82%
Authority and reliability
4.5/5
Expert rating
Real-world application tested