Parts of Speech
Prepositions
Prepositions need an object — never leave them dangling at the end without one in formal writing.
Why this happens
Preposition errors come from direct translation, fixed-phrase memorisation gaps, or uncertainty about time versus place versus abstract relations. Writers mix in/on/at for time, or choose between interested in and good at by ear alone. In formal essays, wrong prepositions make otherwise strong sentences sound non-native or careless.
See it in a sentence
IncorrectShe is good in mathematics and interested on science.
CorrectShe is good at mathematics and interested in science.
Teaching note: Good at and interested in are fixed patterns — the preposition is not interchangeable.
IncorrectWe will meet in Monday at the afternoon.
CorrectWe will meet on Monday in the afternoon.
Teaching note: Days take on; parts of the day usually take in (in the afternoon).
IncorrectThe report depends from accurate data.
CorrectThe report depends on accurate data.
Teaching note: Depend on is the standard collocation, not depend from.
More examples
Different from is preferred in many style guides; different than is common in speech.
In formal writing, different from the control group is safer than different than.
We arrived at the station but arrived in London.
Arrive at a point (station); arrive in a city or large area (London).
Between two options; among three or more.
Between the two candidates is precise; among the finalists fits a larger set.
Composed of ingredients vs composed by a musician.
Of shows makeup; by shows the creator — preposition choice changes the relationship.
Quick check
She has been married with a doctor for ten years.
Show the fix
She has been married to a doctor for ten years. Married to is the correct preposition for a spouse.
Practice this topic in Wrytesmart
Open the grammar workspace to complete interactive exercises for prepositions. You will spot errors, fill blanks, and transform sentences — always with teaching notes that explain the principle, not just the correction.
Master prepositions in context
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