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TOEIC Part 5 Grammar

Why “He Runs Quick” Is Wrong — TOEIC Grammar That Traps You

For the standard written-English contrast practised here, quick is the adjective and quickly is the adverb.

Adverbial quick appears in informal or non-standard usage, but a sentence such as He runs ___ needs quickly in standard written English because the word describes how the action happens.

The grammar decision

Core grammar rule: Use quick to describe a noun or a subject after a linking verb. Use quickly to describe how an action happens.

Quick = adjective

It describes a person, thing, response, decision, repair, change or other noun. It can appear before a noun or after a linking verb.

Patterns: a quick reply · the reply was quick

Quickly = adverb

It describes how an action is performed or how a change happens. Find the verb whose speed is being described.

Patterns: reply quickly · prices changed quickly

Do not choose from the idea of speed

Both words relate to speed, so meaning alone cannot decide the answer. The sentence structure decides whether the blank needs an adjective or an adverb.

The customer service team gave a quick response to the complaint.

Anchor: response is a noun. The adjective quick describes that noun.

The customer service team responded quickly to the complaint.

Anchor: responded is the action. The adverb quickly explains how the team responded.

The manager made a quick decision after reviewing the proposal.

Anchor: decision is the noun being described.

The manager decided quickly after reviewing the proposal.

Anchor: decided is the action being described.

The pattern many learners miss: linking verbs

Quick does not only appear before a noun. It can also describe the subject after a linking verb such as be, seem, become or remain.

The response was quick.

Why: was links quick back to the noun response. No action is being modified.

The recovery seemed quick.

Why: seemed links the adjective to the subject recovery.

The market recovered quickly.

Why: recovered is an action or process. Quickly describes how it happened.

Use the grammar frame around the blank

Adjective frames

a ___ response
the ___ inspection
the service was ___
the change seemed ___

Adverb frames

responded ___
completed the inspection ___
solved the problem ___
changed ___

MTC checking order: Check for a noun, a linking verb, or an action verb. Then choose the word form. Do not start with the general meaning “fast.”

Be careful with “very”

Very does not decide the answer by itself because it can strengthen both an adjective and an adverb.

It was a very quick meeting.

Why: quick describes the noun meeting.

The team responded very quickly.

Why: quickly describes the action responded.

Quick TOEIC-style self-check

The five-question self-check is retained from the supplied page. Choose the form required by the sentence structure. This is local practice, not a score test.

1. The receptionist gave visitors a ___ explanation of the new check-in system.
2. The IT department resolved the network issue ___.
3. The marketing team held a ___ meeting before the product launch.
4. Orders placed before noon are usually processed ___.
5. The response from the supplier was surprisingly ___.

The mistake fast readers can make

If you choose only from the general idea of speed, you can miss the grammatical job of the blank. Quick and quickly are related in meaning, but they do different jobs in the standard-English contrast practised here.

Weak decision

“The sentence is about speed, so I will choose the word that sounds natural.”

Reliable decision

“Does the blank describe a noun or linked subject, or does it modify an action?”

MTC quick check: Noun or linked subject = quick. Action = quickly. Treat this as a checking tool for this focused contrast, not as a rule for every adjective and adverb in English.

If this mistake keeps repeating

One missed item is not enough to establish a Learning Block. If the same adjective/adverb decision breaks down across several Part 5 questions, timed sets or study sessions, review both the grammar and the order in which you check the sentence.

Review your Learning Blocks Check your TOEIC study plan
FAQ (EN) — Why “He Runs Quick” Is Wrong 1. Q: Why is “He runs quick” wrong? A: Because “runs” is an action. You need an adverb to describe it. The correct sentence is “He runs quickly.” 2. Q: What’s the difference between “quick” and “quickly”? A: “Quick” describes a thing (e.g., a quick meeting). “Quickly” describes an action (e.g., leave quickly). 3. Q: When do I use words ending in “-ly”? A: Use “-ly” words when describing how something is done. Example: “She answered clearly.” 4. Q: Can I say “She speaks fluent English”? A: No. You should say “She speaks fluently” or “She is fluent in English.” 5. Q: Why is “He answered correct” wrong? A: “Answered” is an action. You need an adverb: “He answered correctly.” 6. Q: Is “fastly” a real word? A: No. “Fast” is both an adjective and adverb. Use “He runs fast,” not “fastly.” 7. Q: What does TOEIC test with words like “clear” and “clearly”? A: TOEIC tests whether you know when to describe a thing (use “clear”) or an action (use “clearly”). 8. Q: Is “He explained it polite” correct? A: No. You need the adverb: “He explained it politely.” 9. Q: Why does TOEIC use “efficient” and “efficiently” in questions? A: To test if you recognize whether the sentence describes a method (action = “efficiently”) or quality (thing = “efficient”). 10. Q: How do I choose between “quiet” and “quietly”? A: “Quiet” describes something (e.g., a quiet room). “Quietly” describes how something is done (e.g., speak quietly). 11. Q: Can “hard” be used like an adverb? A: Yes. “She works hard” is correct. “Hardly” means “almost not at all,” which is different. 12. Q: What’s the difference between “late” and “lately”? A: “Late” means after the expected time. “Lately” means “recently.” Example: “He arrived late.” vs. “Lately, he’s been tired.” 13. Q: Why do I get confused by “clear” and “clearly”? A: Because they both look similar. Remember: use “clearly” when describing actions like speaking or explaining. 14. Q: Is “The teacher speaks calm” okay? A: No. It should be “The teacher speaks calmly.” 15. Q: Can I say “The report is clearly”? A: No. That’s describing the report, not an action. Use “The report is clear.” 16. Q: What does “She smiled polite” mean? A: It’s incorrect. Use “She smiled politely” to describe how she smiled. 17. Q: How can I tell if I need an adjective or adverb in TOEIC? A: Look at what’s being described. If it’s an action, use the “-ly” adverb form. 18. Q: Is “The device works good” wrong? A: Yes. The correct phrase is “The device works well.” “Well” is the adverb of “good.” 19. Q: Why does TOEIC include fake words like “fastly”? A: To trick you. “Fastly” looks right, but it’s wrong. “Fast” is already correct as an adverb. 20. Q: What’s the fastest way to check if I picked the right word? A: Ask yourself: “Is this describing how something is done?” If yes, use the adverb with “-ly.”