🎯 TOEIC Part 5: Mastering Word Forms for Faster, Higher Scores

In Part 5, you’ll often see four answer choices that look almost identical. The difference? Their form — noun, verb, adjective, or adverb.

If you don’t know which form fits the grammar, you can understand every word in the sentence and still get it wrong.

🧠 What’s a Word Family?

A word family is a group of related words built from the same base but with different endings and roles:

  • success (noun)

  • succeed (verb)

  • successful (adjective)

  • successfully (adverb)

The meaning is connected, but the grammar function changes — and TOEIC loves to test whether you can spot the right one in context.

❌ Why Test Takers Miss These

Many focus on meaning, not grammar role.
But in Part 5, the blank’s role in the sentence decides the answer — not which word “sounds good.”

Example:

The company’s recent ______ led to a major contract.
A) succeed
B) successful
C) success ✅
D) successfully

Why C? The blank follows “recent,” which needs a noun. Only success fits.

🔍 Common Word Form Patterns in TOEIC

  • After a preposition → usually a noun.

  • Before a noun → usually an adjective.

  • After “to” → usually a verb.

  • Between subject and main verb → often an adverb.

📚 High-Frequency Word Families

These appear often in Part 5:

  • apply / application / applicable

  • decide / decision / decisive / decisively

  • approve / approval / approving

  • perform / performance

  • compete / competition / competitive / competitively

  • manage / management / managerial / manager

📝 Sample Question

The board was impressed with the applicant’s ______.

A) decide
B) decision ✅
C) decisive
D) decisively

Why B? After the preposition with, you need a noun — decision.

✅ How to Train This Skill

  1. Spot the signal — check what’s before and after the blank.

  2. Label the role — subject, object, modifier, verb?

  3. Eliminate wrong forms — cross out verbs if you need a noun, etc.

  4. Test it in the sentence — read aloud to confirm it flows.

📈 Why TOEIC Uses Word Form Questions

They test:

  • Your grammar awareness under time pressure.

  • Your ability to process business English structure quickly.

They’re short, frequent, and easy points — if you’ve trained for them.

Final Word

Part 5 word form questions aren’t vocabulary tests — they’re grammar-in-context tests.

Train your eyes to see roles, not just meanings, and you’ll answer faster, with higher accuracy.

For more strategies and resources to master TOEIC grammar under pressure, visit the English Library Collection and start locking in word form accuracy today.

Q1: What’s the difference between “success” and “successful”? A1: “Success” is a noun. “Successful” is an adjective. Example: She had great success. ✅ (noun) She is a successful person. ✅ (adjective) Q2: How do I know when to use a noun vs a verb? A2: Look at the grammar around the blank. After “the” or “a,” you usually need a noun. After “to,” you usually need a verb. Q3: What part of speech usually comes after a preposition like “with” or “by”? A3: A noun. Example: He was praised by the manager. → “manager” is a noun. Q4: What’s the trick to solving word family questions in Part 5? A4: Don’t guess based on word meaning. Look at the sentence structure. Eliminate options that don’t match the grammar role (verb, noun, etc). Q5: Is “decide” a noun or a verb? A5: “Decide” is a verb. The noun form is “decision.” Example: They will decide tomorrow. ✅ It was a difficult decision. ✅ Q6: What’s the adverb form of “successful”? A6: “Successfully.” Example: She successfully launched the product. Q7: Are word families common in TOEIC Part 5? A7: Yes — they appear in almost every test. TOEIC often gives you four options from the same family and tests your grammar knowledge, not just vocabulary. Q8: Can I just memorize which form is right? A8: Not reliably. TOEIC changes the sentence. You need to understand why a noun or verb fits based on the sentence pattern. Q9: What if two options seem possible? A9: Double-check what comes before and after the blank. That will tell you what part of speech is needed. Q10: Is it better to learn word families as groups? A10: Yes. Instead of learning words one by one, group them by form — verb, noun, adjective, adverb — and practice switching between them in full sentences.
A colour image of people in a test room taking a test.