The technician needs to ____ the cause of the malfunction before ordering parts. The options are ascertain, verify, confirm, and establish. A learner who reads all four as "make sure" can stall, because each looks plausible in front of "the cause." The intended answer is ascertain — to find something out that is not yet known. This guide sorts the fact-determination verbs so the choice rests on what the sentence does to the fact, not on which verb sounds most official.
Four verbs, one idea of "finding out," different acts
All four deal with the truth of something, but they frame the act differently — and Part 5 lives on that framing.
ascertain → find something out that is not yet known ("ascertain the cause," "ascertain whether it is safe")
verify → check that a claim or figure is actually true ("verify the data," "verify the identity")
confirm → make certain of something already expected or arranged ("confirm the booking," "confirm attendance")
establish → prove or set up as an accepted fact ("establish a link," "establish the facts")
Ascertain is about discovering an unknown; verify is about checking a stated claim against reality; confirm is about removing doubt from something already anticipated; establish is about proving something firmly enough that it stands as fact. Same territory — the truth — but different acts.
The one-second test: discover, check, reassure, or prove?
You do not need to weigh nuance first. Read what the subject is doing to the fact:
- The subject is finding out something not yet known → ascertain.
- The subject is checking whether a stated claim is true → verify.
- The subject is making certain of something already expected → confirm.
- The subject is proving or setting something up as fact → establish.
Please ____ your email address by clicking the link we sent. That is checking that a stated claim is genuine, so the answer is verify, not ascertain. The study helped ____ a connection between diet and sleep. That is proving something as fact, so establish fits. Read the act, and the verb decides before any question of formality arises. For the wider skill of reading whether an item tests meaning at all, see word choice versus word form.
Verify versus confirm: the overlap that costs points
The two blur because both remove doubt. The split is real: verify checks an unproven claim against evidence, while confirm makes certain of something already expected or arranged.
The bank must **verify** the customer's income before approving the loan.✓ — check an unproven claim against evidence.The airline emailed to **confirm** the flight departs at 9 a.m.✓ — make certain of something already arranged.
When the subject is testing whether a claim holds up, verify fits. When the subject is closing the loop on something already set — a booking, a time, an attendance — confirm fits. TOEIC exploits this by offering both and letting the direction — testing an open claim versus settling a known plan — tip the answer. Matching the verb to what the sentence actually describes rather than defaulting to whichever option looks most business-like is the same instinct that separates a strict standard from a rigorous one: context, not prestige, decides.
Why "establish" is the proof word, not the routine-checking word
Establish is the distractor that punishes reading "make sure" without checking whether the sentence is about proving something. It means to prove or set something up firmly enough that it becomes an accepted fact — and it usually takes an abstract object like a link, a cause, a precedent, or the facts:
The investigation aims to **establish** the sequence of events.✓ — set the facts up firmly.Researchers **established** a clear correlation between the two.✓ — prove it as fact.
It does not fit a routine office check. The receptionist will ____ your appointment for Tuesday is settling something already arranged, so confirm fits, not establish. Reserve establish for sentences where the act is proving or founding something, not merely double-checking a booking. This mirrors the way a near-synonym can share meaning yet resist a given slot — the same trap as the collaborate versus corroborate pair, where surface similarity hides a real difference in use.
Quick reference
| Verb | Core act | Typical object | Sample blank |
|---|---|---|---|
| ascertain | find out the unknown | the cause, whether, the extent | "____ the cause of the delay" |
| verify | check a claim is true | the data, identity, income | "____ the applicant's income" |
| confirm | settle something expected | the booking, attendance, a time | "____ your reservation" |
| establish | prove or set up as fact | a link, precedent, the facts | "____ a link between the two" |
Practice reading the act, not the register
Work through each blank by naming the act before you look at the options:
The auditor could not ____ whether the receipts were genuine.→ checking a claim against evidence → verify.We need to ____ how many attendees to expect.→ finding out an unknown number → ascertain.The court's ruling helped ____ an important legal precedent.→ proving/founding a fact → establish.Could you ____ that you received the package?→ settling something already expected → confirm.
The verb that wins is the one whose act matches the sentence — discover, check, reassure, or prove. When two look right, ask whether the fact is still open (verify) or already arranged (confirm), and whether the sentence merely checks it or actually proves it (establish). That question, not the search for the most formal-sounding word, is what Part 5 rewards. For a full map of how meaning-based items differ from form-based ones, revisit word choice versus word form and drill the distinction until naming the act becomes automatic.