There is a rule most candidates carry into Part 5 that is right often enough to be dangerous: if the word modifies a verb, choose the adverb. It handles a huge share of -ly items correctly, so it never gets questioned — until the test writers put a linking verb in front of the blank and the rule quietly hands you the wrong answer. The results seemed ____ does not want accurately; it wants accurate. The verb is right there, and the adverb is still wrong. This item type is common in Part 5, and the fix is a single mechanical test you apply before you reach for the -ly form.
Why the "modifies a verb" rule breaks
The rule is incomplete, not false. An adverb modifies a verb when the verb describes an action that can be done in a certain manner: She reviewed the contract carefully. But some verbs do not describe an action at all — they link the subject to a description of the subject. In The proposal is complete, complete is not describing how the proposal does something. It is describing what the proposal is. That describing word points back at the subject, and words that describe a noun are adjectives.
So the real question is never "is there a verb here?" It is "is this verb linking the subject to a description of itself, or is it an action being performed?" Get that classification right and the part of speech follows automatically.
The two-second test: replace with "is"
For any blank sitting right after a verb, mentally replace the verb with a form of be. If the sentence still makes sense, the verb is a linking verb and the blank wants an adjective.
The equipment remained ____.→ "The equipment is ___." → sensible → linking verb → adjective (operational, notoperationally).The manager responded ____.→ "The manager is __." → the manager _is what? This does not describe a state of the manager; it describes how they responded → action verb → adverb (promptly, notprompt).
The test works because linking verbs are, functionally, equals signs. become, seem, remain, stay all reduce to "is/was, in a slightly different flavor." Action verbs do not survive the substitution.
The linking verbs TOEIC actually uses
Memorize this short set. When the verb before the blank is one of these, the default answer is the adjective:
- be (
is,are,was,were,been,being) - seem, appear
- become, grow, turn (in the "turn cold" sense)
- remain, stay, keep (in "keep quiet")
- the sense verbs: look, feel, sound, taste, smell
Note the sense verbs especially. The proposal looks ____ takes promising (adjective), not promisingly. The plan sounds ____ takes reasonable, not reasonably. These are the highest-value traps because "looks" and "sounds" feel like actions, so the adverb looks tempting.
The disguise: verbs that are linking sometimes, action other times
The dangerous cases are verbs that flip roles depending on meaning. appear, grow, turn, prove, and the sense verbs can all be either.
- Linking:
The report proved ____ accurate→ describes the report → adjective. - Action:
The consultant proved the theory ____→ describes how the theory was proven → adverb (conclusively).
The "replace with is" test cuts through this every time. The report **is** accurate works → adjective. The consultant **is** the theory conclusively is nonsense → adverb. Do not classify the verb from a memorized list alone when it is one of these swing verbs; run the substitution on the actual sentence.
The distractor pattern the writers rely on
A typical Part 5 linking-verb item offers four forms of the same root: an adjective, an adverb, a noun, and often a verb form — for example success, successful, successfully, succeed. The adverb successfully is placed there specifically to catch candidates running the "modifies a verb" rule on autopilot. The moment you see a -ly form as an option right after seem, become, remain, or a sense verb, treat it as the trap until the "is" test proves otherwise.
A note on adjectives after the object
One extension trips people who have mastered the basic rule. Some action verbs take an object and then an adjective describing that object — the object complement pattern: Keep the workspace ____ (clean, not cleanly), The audit found the accounts ____ (accurate, not accurately). Here the adjective describes the object, not the verb. Test it by asking whether the last word describes the noun right before it. The workspace is clean → adjective. This pattern appears less often than the linking-verb case but uses the same underlying logic: adjectives describe nouns, wherever the noun happens to sit.
Drill it, don't just read it
This is a recognition skill, and recognition only sticks under timed pressure. Work through mixed sets where linking-verb items and ordinary action-verb items are shuffled together, so you cannot coast on a pattern — every blank forces the "replace with is" decision fresh. For the underlying part-of-speech identification that this test depends on, review the Part 5 word-family and part-of-speech slotting fundamentals, and pair this with the broader Part 5 subject-verb agreement discipline so that once you have the right part of speech, the form still agrees with the rest of the sentence.
The one-line takeaway
Before you choose the adverb because "there's a verb," run the is test. If "the subject is [word]" makes sense, the verb is linking and the blank is an adjective — no matter how much the -ly form wants to be picked.