Engineers confirmed that the bridge design is technically ____, though its long-term cost remains uncertain. The options are feasible, viable, practicable, and workable. A learner who reads all four as "possible" can stall, because each looks plausible in front of "the design." The intended answer is feasible — possible to do in principle. This guide sorts the feasibility adjectives so the choice rests on which kind of possibility the sentence tests, not on which word sounds most technical.
Four adjectives, one idea of "possible," different angles
All four say something can be done, but they frame the possibility differently — and Part 5 lives on that framing.
feasible → possible to do in principle; capable of being achieved ("technically feasible," "a feasible target")
viable → able to succeed, survive, or stay profitable over time ("a viable business," "commercially viable")
practicable → possible to carry out under real conditions ("as far as practicable," "a practicable method")
workable → good enough to function in practice; usable ("a workable solution," "a workable compromise")
Feasible asks whether something can be achieved at all; viable asks whether it can last or pay off; practicable asks whether it can actually be carried out on the ground; workable asks whether it functions well enough to use. Same territory — possibility — but different tests.
The one-second test: achievable, sustainable, executable, or serviceable?
You do not need to weigh nuance first. Read which kind of "possible" the sentence is testing:
- Can it be achieved in principle at all → feasible.
- Can it succeed or survive over time → viable.
- Can it be carried out under real conditions → practicable.
- Does it function well enough to use → workable.
The plan is technically ____, but no investor believes it will ever turn a profit. That contrast points to survival and profit, so the answer is feasible for the first half and the sentence sets it against not being viable. The committee reached a ____ compromise after hours of debate. That is a solution good enough to function, so workable fits. Read the kind of possibility, and the adjective decides before any question of register arises. For the wider skill of reading whether an item tests meaning at all, see word choice versus word form.
Feasible versus viable: the overlap that costs points
The two blur because both describe something that "can work," but the split is real: feasible asks whether it can be done at all, while viable asks whether it can succeed or last once done.
A single-span bridge is **feasible** given the soil conditions.✓ — it can be built in principle.The route is only **viable** if passenger numbers stay above a certain level.✓ — it can survive/pay off over time.
When the question is about achievability — can we build it, can we reach the target — feasible fits. When the question is about sustainability, profit, or survival, viable fits. TOEIC exploits this by offering both and letting a phrase like "long-term," "commercially," or "profitable" tip the answer toward viable. Matching the adjective to the kind of possibility rather than defaulting to whichever option looks most business-like is the same instinct that separates the eligibility adjectives: the precise condition, not prestige, decides.
Why "practicable" is the real-conditions word, not the feels-doable word
Practicable is the distractor that punishes reading "possible" without checking whether the sentence is about carrying something out under actual conditions. It means capable of being done in practice, given the real constraints of time, resources, and circumstances — and it often appears in the fixed phrase as far as practicable or where practicable:
Staff should recycle waste where **practicable**.✓ — wherever real conditions allow it.The evacuation route must be **practicable** in poor weather.✓ — able to be carried out under real conditions.
It does not fit an abstract judgement about whether an idea could succeed. The proposed merger is not ____ without stronger cash flow is about survival, so viable fits, not practicable. Reserve practicable for sentences about actual execution under constraints, not about whether a plan is a good bet. This mirrors the way a near-synonym can share meaning yet resist a given slot — the same trap as the practical versus practicable pair, where surface similarity hides a real difference in use.
Quick reference
| Adjective | Core question | Typical collocation | Sample blank |
|---|---|---|---|
| feasible | can it be achieved at all | technically, economically | "____ within the budget" |
| viable | can it succeed or last | commercially, financially | "a ____ business model" |
| practicable | can it be carried out now | as far as, where, in practice | "recycle where ____" |
| workable | does it function enough | a solution, compromise, plan | "a ____ compromise" |
Practice reading the test, not the register
Work through each blank by naming which kind of possibility it tests before you look at the options:
The rescue plan must be ____ even when the power fails.→ carried out under real conditions → practicable.Analysts doubt the airline is ____ without a government subsidy.→ able to survive/pay off → viable.Landing a probe on the comet is now technically ____.→ achievable in principle → feasible.After negotiation, the two sides found a ____ arrangement.→ good enough to function → workable.
The adjective that wins is the one whose kind of possibility matches the sentence — achievable, sustainable, executable, or serviceable. When two look right, ask whether the sentence tests getting it done at all (feasible), keeping it alive (viable), running it under real constraints (practicable), or merely making it function (workable). That question, not the search for the most technical-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 kind of possibility becomes automatic.