Prepositions are the most under-prepared category on TOEIC Link Part 5, and the reason is psychological rather than linguistic. Candidates who would never skip a verb-tense drill will happily skip preposition practice because prepositions feel like something you either know or you don't — a matter of intuition, not study. That belief is wrong, and it is expensive. Preposition items are not random; they cluster around a small set of confusion pairs, and once you can name the pair, the answer is almost always recoverable from a rule rather than a feeling.
This guide covers the five pairs that account for the overwhelming majority of preposition errors on Part 5. For each pair we give the distinction, the business-context trap, and a one-line test you can apply at the moment of choice.
Why preposition items are mispriced by test-takers
A preposition item costs the same single point as a relative-clause item, but candidates spend a fraction of the preparation time on it. The result is a category where effort and reward are badly misaligned: a few hours of targeted study on confusion pairs typically moves preposition accuracy more than the same hours spent anywhere else, because you are starting from a lower base.
The other reason preposition items are mispriced is that they look easy. The sentence is usually short, the vocabulary is familiar, and three of the four options are obviously wrong. That surface simplicity makes candidates answer fast and move on — which is exactly when the one engineered distractor catches them. Slowing down by three seconds on a preposition item is one of the highest-return habits you can build, and it pairs naturally with the broader pacing discipline covered in our TOEIC Link error analysis and mistake tracking guide.
Pair 1: in / on / at for time
The classic hierarchy still holds, and it is worth re-anchoring because the test relies on candidates being fuzzy on the boundaries.
- at — precise points: at 9:00, at noon, at the start of the meeting
- on — days and dates: on Monday, on July 3, on the deadline date
- in — longer spans: in June, in 2026, in the third quarter
The business trap is the phrase that sounds like one category but is conventionally another. In the morning but at night. On the weekend (US) versus at the weekend (UK) — TOEIC Link will not test the dialect split, but it will test on time versus in time, which mean different things: on time = punctual; in time = before a deadline with margin to spare.
One-line test: Ask whether the time reference is a point (at), a calendar unit of a day (on), or a span longer than a day (in).
Pair 2: by / until
This is the single most lucrative preposition pair on the test because the distinction is rule-based and the error is consistent.
- by — completion no later than a deadline (a single action): Submit the report by Friday.
- until — continuation up to a point in time (an ongoing state): The office is closed until Monday.
The trap option swaps them: The report must be finished until Friday is wrong; it should be by Friday. If the verb describes a single completed action, you want by. If it describes something that continues and then stops, you want until.
One-line test: Can you replace the verb with "stop doing X at this time"? If yes → until. If the verb is a one-time completion → by.
Pair 3: for / during
Both relate to duration, but they answer different questions.
- for + length of time: for three hours, for two weeks, for the duration of the project
- during + a named event or period: during the meeting, during Q3, during the renovation
The test trap is using during with a number — during three hours is wrong. If a quantity of time follows the blank, you almost always want for. If the name of an event or period follows, you want during.
One-line test: Number after the blank → for. Named event after the blank → during.
Pair 4: between / among
A relationship pair that crosses into place and abstraction.
- between — two distinct parties, or several parties considered individually: between the buyer and the seller, the agreement between the three departments
- among — within a group considered collectively: popular among employees, distributed among the team
The modern style guides have relaxed the "between = exactly two" rule (you can say between the four offices when each pairwise relationship matters), but TOEIC Link tends to test the clean cases: two named parties → between; an undifferentiated group → among.
One-line test: Are the parties named and distinct? → between. Is it an unnamed collective? → among.
Pair 5: over / above (and the place set in/on/at)
For place, the same in/on/at logic applies — at the reception desk (point), on the third floor (surface/level), in the building (enclosed space) — but the pair that actually gets tested is over / above.
- over — directly above with coverage or movement across: a bridge over the river, revenue over the last quarter
- above — at a higher level, often a threshold: above the target, temperatures above average
In business contexts, over frequently means "more than" with a span (over 500 units), while above means "exceeding a reference line" (above the quota). Both can express "more than," so read the surrounding nouns: a measured span pulls over; a threshold or benchmark pulls above.
One-line test: Movement or coverage across → over. A reference line being exceeded → above.
Putting the five pairs into one decision sequence
When you hit a preposition item, do not search your intuition. Run this sequence:
- Is it time or place? This halves your search space immediately.
- Which confusion pair is being tested? Name it. Nine times out of ten it is one of the five above.
- Apply the one-line test for that pair. The test is mechanical and does not depend on how the sentence "sounds."
- Confirm by elimination. The trap option is usually the other member of the pair; once you have applied the test, that option should feel actively wrong, not merely less right.
This is the same name-the-pattern-then-apply-the-rule discipline that underlies the rest of the Part 5 grammar series — see the companion treatments of comparatives and superlatives and conjunctions and connectors for the same approach applied to other categories.
A note on collocations
A subset of preposition items are not really about time or place at all — they are fixed verb + preposition or adjective + preposition collocations: depend on, responsible for, interested in, comply with, consistent with. These cannot be reasoned out from the five pairs; they have to be learned as units. The good news is that the business-English collocation set is small and high-frequency. Keep a running list in your error log, and treat each collocation miss as a vocabulary item rather than a grammar item, so it enters your spaced-review cycle instead of being re-derived under pressure.
The bottom line
Preposition accuracy on TOEIC Link Part 5 is not a matter of native-speaker feel. It is a matter of recognizing which of five confusion pairs you are looking at and running a single mechanical test. Candidates who internalize this stop guessing on the category that they were previously most likely to guess on — and they recover the points that the surface simplicity of these items had been quietly costing them.