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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
underline on
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "underline on" is not correct and usable in written English.
It is typically used incorrectly as "underline" does not require the preposition "on." Example: "Please underline the key points in the text."
⚠ May contain grammatical issues
Science
Wiki
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
4 human-written examples
These results underline, on the one hand, how important it is to deal with the issue of violence and aggression towards nursing staff and, on the other hand, they show that other professional groups, who also have frequent contact with the patients, should not be neglected.
Science
They underline, on the other hand, the practical relevance of considering natural variability of the protease complement among L. decemlineata target populations, eventually determinant in the success or failure of cystatin-based control strategies on a large-scale basis.
Science
The primers, with the SNP (bold letters) at the 3' end and an extra mismatched nucleotide (underline) on the third nucleotide from the end are listed in Table 2.
Science
Under assignments list the chores/work you want them to complete such as: Read 30 minutes, Develop Talent 30 Minutes, Room is Clean & Tidy, Daily Jurisdiction, Good Turn, See It - Do It, All Homework Completed, Sweat for 30 Minutes, Dishwasher Loaded and Turned On, etc. Now in each box across the chart draw a short underline on which the teen can sign their initials when the job is completed.
Wiki
Human-verified similar examples from authoritative sources
Similar Expressions
56 human-written examples
This approach should be based on existing standards built around previous experience and benefit from nowadays survey studies that underline on-site problems.
Science
Our results further suggest that efforts to expand PV installation in equatorial developing countries may benefit greatly from policies designed to make low cost finance more widely available, which underlines on-going efforts to "de-risk" low carbon investments.
Science
Their situation underlines, on the one hand, the effectiveness of EU citizenship and the rights framework in Europe and, on the other, the insignificance of national citizenship in the lives of most people, including immigrants.
The frailty of the participants was underlined on Wednesday when one man, 83-year-old Lee Kun-Su, was forced to pull out at the last minute because of health issues.
News & Media
The impact of the Co-operative Bank's troubles on its one-time full owner, the Co-operative Grounderlinedderlined on Monday as the wider group was forced into a complex restructuring of a relatively minor bond.
News & Media
This isolation was underlined on Monday.
News & Media
Mr. de Guindos underlined on Tuesday the importance of Santander.
News & Media
Expert writing Tips
Best practice
When you mean to "underline" something, use the verb "underline" without the preposition "on". For example, say "underline the main points" instead of "underline on the main points".
Common error
Do not add "on" after the word "underline" when your intention is to mark a word or sentence. The verb "underline" does not require a preposition in this context.
Source & Trust
80%
Authority and reliability
2.2/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "underline on" is typically intended to function as a verb indicating emphasis or highlighting. However, it is grammatically incorrect. The correct usage involves using "underline" without the preposition "on", as Ludwig AI suggests.
Frequent in
Science
37%
News & Media
37%
Wiki
26%
Less common in
Formal & Business
0%
Encyclopedias
0%
Reference
0%
Ludwig's WRAP-UP
In summary, while the phrase "underline on" may appear in various contexts, it is generally considered grammatically incorrect. According to Ludwig AI, the verb "underline" does not require the preposition "on". It's more appropriate to use "underline", "emphasize", or "highlight" depending on the context to clearly convey your intended meaning. Although examples exist, following standard grammatical rules will enhance clarity and credibility in your writing.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
underline
Removes the preposition "on", correcting the grammatical error while maintaining the core meaning of highlighting something.
emphasize
Focuses on stressing the importance of something, similar to underlining its significance.
highlight
Indicates marking something to make it stand out, akin to underlining.
underscore
Similar to "underline", this term means to emphasize or stress.
draw attention to
Shifts the focus to directing notice towards something, sharing the emphasis aspect.
stress the importance of
Highlights the critical nature of something, sharing the emphasis aspect.
place emphasis on
Emphasizes the importance of something, similar to highlighting its significance.
call attention to
Draws notice to something, sharing the emphasis aspect but with a slightly broader application.
point out
Highlights a specific detail or fact, related to emphasizing information.
mark
Indicates identifying or highlighting a specific area or text.
FAQs
How can I use "underline" correctly in a sentence?
Use "underline" directly followed by the element you want to emphasize. For example: "Please "underline the key points" in the document".
What can I say instead of "underline on"?
Which is correct, "underline on" or "underline"?
"Underline" is the correct term. The preposition "on" is not needed after "underline" when used as a verb.
Is "underline on" ever correct?
In very specific, technical contexts, "underline on" might appear when describing the action of drawing a line on something. However, in most general writing, just use "underline".
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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
80%
Authority and reliability
2.2/5
Expert rating
Real-world application tested