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Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
an substantial
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "an substantial" is not correct in written English.
It should be "a substantial" because "substantial" begins with a consonant sound. Example: "The project requires a substantial amount of funding to be successful."
⚠ May contain grammatical issues
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
12 human-written examples
Heaney leaves an substantial and important body of work; his poems always had the human touch.
News & Media
Due to the current lack of a premium – not dissimilar to the Fair trade model – RTRS has yet to make an substantial impact on soy farmers in Brazil.
News & Media
If you use these programs in an substantial way, then I request that you make note of this in any publications that results.
Academia
Speaking before a meeting with the prime minister on Thursday afternoon, Victorian premier Denis Napthine said: "I believe the federal government will not only consider a substantial assistance package, but it is imperative that they provide an substantial assistance package".
News & Media
Figure 16 shows that hydraulic units of 1 and 2 in well A, 1 and 2 in well B, and 1 and 2 and 3 in well C have an substantial role on fluid transmissibility.
According to a report issued by the Investment Company Institute and Deloitte, employers are thrusting more of the plan charges onto their employees, with the result that workers are now responsible for 91% of plan expenses, an substantial increase from 2009 when they covered 78% of such charges.
News & Media
Human-verified similar examples from authoritative sources
Similar Expressions
48 human-written examples
"A billion is a substantial number.
News & Media
We made a substantial bid.
News & Media
A substantial and satisfying volume.
News & Media
This is a substantial upgrade".
News & Media
A substantial irony enters here.
News & Media
Expert writing Tips
Best practice
Always ensure the article 'a' or 'an' agrees with the following word's sound. Use 'a' before consonant sounds and 'an' before vowel sounds.
Common error
Avoid using "an" before words that begin with a consonant sound, even if the letter is a vowel. For instance, use "a university" not "an university" because 'university' starts with a 'y' sound.
Source & Trust
60%
Authority and reliability
1.2/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "an substantial" attempts to function as a determiner plus adjective modifying a noun. However, Ludwig AI indicates it is grammatically incorrect because the article "an" is misused. It should be "a substantial" instead.
Frequent in
Science
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News & Media
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Formal & Business
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Less common in
Science
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News & Media
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Formal & Business
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Ludwig's WRAP-UP
In summary, the phrase "an substantial" is grammatically incorrect. As Ludwig AI points out, the correct usage is "a substantial" because "substantial" begins with a consonant sound. This error can affect the clarity and credibility of your writing. Remember to always match the article (a/an) to the sound of the following word. While there aren't examples of "an substantial" in Ludwig's data, understanding this basic grammar rule will help you avoid similar mistakes. Using alternatives such as "a significant" or "a considerable" can also improve your writing.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
a substantial amount
Corrects the article usage; "a" precedes a consonant sound.
a considerable quantity
Replaces "substantial" with "considerable" while maintaining the correct article.
a significant portion
Uses "significant" instead of "substantial" with correct article usage.
an important element
Employs "important" with the appropriate article "an", shifting the emphasis.
a large segment
Substitutes "substantial" with "large", keeping the article "a".
a sizable chunk
Uses "sizable" as a replacement with article "a".
a noteworthy component
Replaces with "noteworthy", using the grammatically correct "a".
a meaningful contribution
Substitutes "substantial" with "meaningful" and the correct article.
a marked degree
Uses "marked" and retains the article "a" to correct the grammar.
a material part
Replaces "substantial" with "material", ensuring proper article usage.
FAQs
What's the correct way to say "substantial" with an article?
The correct way is to use "a substantial" because the word "substantial" begins with a consonant sound.
Why is "an substantial" grammatically incorrect?
The article "an" is used before words that start with a vowel sound. Since "substantial" starts with the consonant sound /s/, the correct article is "a substantial".
What alternatives can I use that correctly use the article "an"?
While not a direct synonym, you could rephrase your sentence to use words like "an important" or "an essential" component, if the context allows.
How can I avoid making mistakes with articles like "a" and "an"?
Focus on the sound at the beginning of the word, not just the letter. If the word starts with a vowel sound (like 'hour'), use "an". If it starts with a consonant sound (like 'house'), use "a house".
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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
60%
Authority and reliability
1.2/5
Expert rating
Real-world application tested