🔍 Mastering Modal Verbs for TOEIC Success: Can, Could, Might & More

If you’ve ever been puzzled by the difference between “must” and “have to” or found yourself hesitating over “should” versus “ought to,” you're not alone. Modal verbs may seem small, but they carry big meaning—especially in the TOEIC test. From expressing obligation to hinting at possibility or offering polite advice, these compact helpers show up everywhere in business communication and Part 5 grammar questions.

📌 What Are Modal Verbs?

Modal verbs—such as can, could, may, might, must, shall, should, will, and would—modify the meaning of the main verb that follows. They do not take “-s,” “-ed,” or “-ing” endings, and they are always followed by the base form of a verb (e.g., can go, should attend, might improve).

In the TOEIC test, modals appear in subtle grammar traps, often testing your ability to spot errors in tense consistency, formality, or nuance.

📈 Why Modal Verbs Matter on TOEIC

In a workplace email, a sentence like:

“You must submit the report by Friday.”

is different in tone and urgency from:

“You should submit the report by Friday.”

Understanding that must expresses strong obligation while should gives a suggestion could be the difference between a correct answer and a costly mistake.

TOEIC Part 5 often includes incomplete sentences like:

“Employees ___ attend the training to comply with company policy.”

A tempting choice might be “should,” but the correct answer might be “must” if the sentence implies a requirement. These are the small distinctions TOEIC loves to test.

🤔 Common Modal Uses and Traps

  • Can / Could – Ability or possibility. Can is present or general. Could is more polite or past possibility.

    “I can meet tomorrow.” / “He could finish it by noon if needed.”

  • May / Might – Uncertainty or permission. May is slightly more formal.

    “It may rain later.” / “You may leave early today.”

  • Must / Have to – Necessity or strong obligation.

    “Staff must wear ID badges.”
    TOEIC often tests these two as near-synonyms—but be careful with tense.

  • Should / Ought to – Advice or weak obligation.

    “You should double-check the figures.”
    Both are acceptable, but “should” is more common in TOEIC.

  • Would – Hypotheticals and polite offers.

    “I would recommend the newer model.”

⚠️ Classic TOEIC Pitfalls

  1. Tense mix-ups:
    “He must submitted the form.” → ❌ Wrong
    “He must have submitted the form.” → ✅ Correct

  2. Incorrect base form:
    “She should to leave.” → ❌
    “She should leave.” → ✅

  3. Misinterpreting tone or strength:
    Choosing “can” when the sentence requires “must” leads to misunderstanding the level of necessity.

📝 Final Tip

Mastering modal verbs isn’t just about memorizing rules—it’s about understanding the intention behind the sentence. Ask yourself, “Is this about permission, obligation, advice, or possibility?” That one question can often guide you to the correct choice in a TOEIC question.

In business English and the TOEIC exam, modal precision equals clarity—and clarity is key to success.

🔒 Hidden FAQs — Modal Verbs (English) What is the main function of modal verbs? Modal verbs modify the meaning of the main verb, expressing ability, permission, obligation, or possibility. Do modal verbs take “-s” in third person singular? No. Modals never change form based on subject. We say “She can go,” not “She cans go.” Can you use 'must' in the past tense? No direct past form exists, but “must have + past participle” expresses past certainty. Example: “She must have forgotten.” What's the difference between 'can' and 'could'? 'Can' is for present or general ability. 'Could' can mean past ability or a more polite suggestion. Is 'should' the same as 'must'? No. 'Should' is advice; 'must' expresses obligation or strong necessity. Why is 'may' more formal than 'can'? 'May' is often used in formal settings to express permission. Example: “You may leave early.” Can I say 'should to' or 'must to'? No. Modals are always followed by the base form: “should go,” “must finish,” etc. What does 'might have' mean? It shows possibility in the past. Example: “He might have missed the train.” What is the negative form of 'must'? 'Must not' means prohibition. Example: “You must not smoke here.” Is 'have to' a modal verb? Not technically—it behaves like one and often replaces 'must' in spoken English. What is the polite form of 'can'? 'Could' is used for polite requests or offers. Example: “Could you help me with this?” Why is 'would' used for hypothetical situations? 'Would' shows imagined or unlikely conditions. Example: “I would travel more if I had time.” Can modal verbs be used in passive voice? Yes. Example: “The report must be submitted by noon.” What is the difference between 'shall' and 'will'? 'Shall' is formal or legalistic; 'will' is standard for future intentions. Is 'ought to' commonly used in TOEIC? Less commonly than 'should', but it appears in reading sections occasionally. What’s the meaning of 'must have been'? It implies past certainty. Example: “He must have been tired.” How are modals tested in TOEIC Listening? You may hear requests, obligations, or suggestions—listen for modal clues like “could” or “should.” Can two modals appear together? Not normally. Say “should go,” not “should must go.” What is a modal trap in TOEIC grammar? A distractor that uses incorrect tense or form, like “can to speak” instead of “can speak.” Why do TOEIC questions often mix modal verbs with deadlines? To test whether you understand tone, formality, and level of urgency in business settings.