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TOEIC Link Part 5: by versus until

"By" and "until" both attach to a future time, but they answer different questions: "by" marks the deadline for a single completed action, while "until" marks how long a continuous situation lasts. Part 5 builds items around that contrast, and the answer turns on whether the verb describes one finished event or an ongoing state. Reading the verb before the blank settles the choice faster than translating the time word.

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TOEIC Link Part 5: by versus until

By and until are a classic Part 5 trap because both point to a future time and both translate into many languages with a single word. In English they split cleanly: by names the deadline for an action that happens once and is then finished, while until names the end point of a situation that continues without interruption up to that moment. The test rewards reading the verb, not the time word — once you know whether the action is a single completed event or a continuous state, the preposition chooses itself.

The core split: deadline versus duration

The decision comes down to one question: does the action happen at a single point on or before the time given, or does it stretch across the whole period leading up to that time?

  • by = no later than this point — used with an action that occurs once. Please submit the report by Friday. The submitting happens at one moment, and Friday is the latest acceptable moment for it.
  • until = continuously up to this point — used with an ongoing action or state. The office stays open until 9 p.m. The staying-open continues across the whole stretch and stops at 9.

A quick test: if you can replace the verb with "the deadline is," use by. If you can replace it with "continues / does not stop," use until. The store is closed until Monday means it stays closed across the whole gap; The store will reopen by Monday means the single act of reopening happens no later than Monday. Same two words, opposite logic, decided entirely by the verb.

Why the verb decides it

Part 5 rarely tells you outright whether an action is one-time or continuous — you read it off the verb's meaning.

  • One-time verbs take by: finish, submit, arrive, complete, return, pay, deliver, respond. These name events that happen and are done. Payment must be received by the end of the month.
  • Continuous or stative verbs take until: stay, remain, wait, continue, last, keep, be open, work. These name conditions that hold across time. Employees must remain until the audit is complete.

When the blank sits in front of a time and the verb is something like complete or submit, by is almost always the answer, and until is the distractor. When the verb is wait or remain, the reverse holds. This is the same "read the structure, not the meaning" habit that runs through all of Part 5 grammar — see our guide to prepositions of time and place for the wider family of time prepositions that work the same way.

The negative twist: "not ... until"

One pattern reliably catches test-takers. A negative verb with until does not mean the action continues — it means the action does not happen before that point and then starts.

The results will not be announced until next week.

This says the announcing happens next week, not before. Learners often want by here ("announced by next week"), but that would mean "no later than next week," which is the opposite — it would allow the announcement to come early. With a negative verb describing a single event that is delayed up to a point, English uses not ... until. Watch for not, won't, or isn't earlier in the sentence; it flips the natural-feeling choice.

"By" with deadlines, "until" with no interruption

Two more contrasts help lock the distinction in.

"By the time" introduces a clause

By also appears in the conjunction by the time, which introduces a full clause and pairs with a perfect tense:

By the time the manager arrived, the meeting had already ended.

Here by the time marks the deadline-point against which another action is measured. Until cannot do this job — it does not introduce this "deadline clause" structure.

"Until" cannot mark a single finished action

A frequent error is Finish it until 5 p.m. This is wrong because finish is a one-time act and until demands a continuous one. The intended meaning — "the latest moment to finish is 5" — requires by: Finish it by 5 p.m. If you ever see until in front of a completion verb, treat it as the trap answer.

A fast decision procedure

On test day, run the blank through three quick checks:

  1. Find the verb. Is it a single completed action (submit, arrive, pay) or a continuous state (stay, wait, remain)?
  2. Single action → by. Continuous → until. This resolves most items immediately.
  3. Check for a negative. If the verb is negated and describes one delayed event, the answer is until even though the verb is "one-time," because of the not ... until pattern.

This verb-first reading is faster and more reliable than translating the time word, which is exactly where the trap is set.

Practice mindset

By versus until rewards drilling because the rule is mechanical once you see it: deadline versus duration, decided by the verb. Pair this with timed repetition on the related time-and-duration contrasts — the since versus for distinction with the present perfect trains the same instinct to read duration off the structure. For the full Part 5 picture, start from what TOEIC Link Part 5 tests and work outward. When the verb-first habit is automatic, by and until stop being a coin flip and become free points.