Choose the Right Preposition
Lesson 16 of 20 Thesis Editing Tips
From the Examiner’s Desk
“I frequently examine theses in which years of excellent research are obscured by weak writing.”
Many writing guides focus on grammar.
This lesson focuses on readability.
Its purpose is to help readers understand your ideas more quickly and with less effort.
As a PhD examiner and thesis editor, I frequently see otherwise excellent theses weakened by one surprisingly small mistake.
Using the wrong linking word.
Grammarians call these words prepositions.
They include words such as in, on, at, of, to, and with.
Although they are small, they play an important role in making your writing sound natural and precise.
Incorrect prepositions rarely change the scientific content of a thesis.
However, they immediately catch the attention of experienced readers and often suggest that English may not be the writer’s first language or that the document has not been carefully proofread.
Fortunately, they are among the easiest mistakes to correct.
What Is a Preposition?
A preposition is a small linking word that shows the relationship between people, places, objects, time or ideas.
For example:
❌ The participants were interested on the study.
✅ The participants were interested in the study.
Only one word has changed.
Yet the sentence immediately sounds more natural.
Commonly Confused Prepositions
In and Into
Use in to describe where something is.
Use into to describe movement.
Examples:
✅ The samples were stored in the freezer.
✅ The samples were placed into the freezer.
On
Use on when something rests on a surface.
Examples:
✅ The microscope was on the bench.
✅ The results are shown on the graph.
Between and Among
Use between when referring to two people or two clearly defined groups.
Use among when referring to more than two people or things.
Examples:
✅ The agreement was reached between the two departments.
✅ The questionnaires were distributed among the participants.
Of
The word of shows a relationship.
Example:
✅ Many of the participants completed the survey.
As you learned in Lesson 15, too many “of” phrases can make writing heavy.
Whenever possible, replace long “of” phrases with shorter expressions.
With
Use with to show association or accompaniment.
Examples:
✅ The patients were treated with antibiotics.
✅ The questionnaire was completed with assistance.
Other Common Examples
Some prepositions are linked to particular words.
For example:
❌ different than
✅ different from
❌ responsible of
✅ responsible for
❌ capable to
✅ capable of
❌ consistent to
✅ consistent with
These combinations may seem illogical, but they are the forms expected in standard academic English.
💬 WhatsApp with Dr Anastasia Apostolides (reasonable hours)
Why Examiners Notice These Mistakes
A single incorrect preposition rarely attracts attention.
Repeated mistakes, however, interrupt the flow of reading and make writing sound less natural.
Many of these errors occur because writers translate directly from another language into English.
One of the best ways to improve is to notice how experienced researchers use these small linking words in published journal articles.
Practical Editing Strategies
When proofreading your thesis:
• Pay special attention to words such as in, on, at, to, for, and with.
• Read the sentence aloud.
• Ask yourself:
“Does this sound natural?”
• If you are unsure, check how the phrase is used in a recent journal article in your discipline.
The more you read well-written academic papers, the more naturally correct prepositions will come to you.
Quick Editing Checklist
Before submitting your thesis, ask yourself:
✓ Have I checked the small linking words in each sentence?
✓ Have I avoided translating directly from another language?
✓ Does the sentence sound natural when read aloud?
✓ Have I checked uncertain expressions against published research?
✓ Would another reader understand my meaning immediately?
Key Takeaway
The smallest words often make the biggest difference.
Choosing the correct preposition improves clarity, readability and professionalism.
You do not need to memorise grammatical terminology.
Simply remember that the correct preposition helps your writing sound natural, confident and easy to read.
Need Professional Thesis Editing?
If you would like an experienced PhD examiner to review your thesis before submission, I’d be happy to help.
Whether you need a complete thesis edit, advice on improving clarity or feedback on a proposal, feel free to get in touch.
Dr Anastasia Apostolides
PhD Examiner • Thesis Editor • Proposal & Academic Consultant
Helping Master’s, MBA, DBA and PhD students write with clarity and confidence.
💬 WhatsApp with Dr Anastasia Apostolides (reasonable hours)
📧 Email: info@uedit.org
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Continue Learning
This article is part of the 20 Thesis Editing Tips series.
Continue to the next lesson or explore the complete collection of free thesis resources to strengthen every stage of your academic writing.