Say What You Mean: Mastering Modals in TOEIC Grammar

If you’ve ever been confused between can and may, or wondered whether to use should or must, you're not alone. Modal verbs are small but powerful — they change the tone, meaning, and intention of your sentence. In TOEIC grammar (especially Part 5), modals are used to test your understanding of necessity, possibility, ability, suggestion, and permission — all without changing the main verb.

Let’s break it down so you don’t get caught by tricky distractors again.

🔹 What Are Modals?

Modals are auxiliary verbs that come before the base form of a main verb. They do not change form — no -s, -ed, or -ing.
Examples:

  • can go, should review, must attend, might be late

🔹 Modals of Ability: Can / Could

Use can for present/future ability or possibility:

  • “I can finish the report by noon.”

  • “We can meet after lunch.”

Use could for past ability or polite suggestions:

  • “She could speak three languages as a child.”

  • “Could you send me the file?”

TOEIC Trap: Using “can” when referring to the past, or mixing formality levels.

🔹 Modals of Obligation: Must / Have to / Should / Ought to

Must = strong obligation (often internal):

  • “You must wear your ID badge.”

Have to = external obligation (rules/laws):

  • “Employees have to submit receipts.”

Should / Ought to = weaker obligation or recommendation:

  • “You should double-check the figures.”

  • “We ought to leave soon.”

TOEIC loves to test the subtle difference between must vs. should — don’t confuse requirement with advice.

🔹 Modals of Permission: Can / May

Can = informal permission:

  • “Can I leave early today?”

May = more formal or polite:

  • “May I speak to Mr. Tanaka?”

In real business emails, may sounds more respectful, which TOEIC favours in tone-based questions.

🔹 Modals of Possibility: May / Might / Could

These express uncertainty — all three are often interchangeable in meaning, but differ slightly in tone.

  • “It may rain this afternoon.”

  • “We might need to revise the schedule.”

  • “She could be at lunch now.”

TOEIC sometimes tests these in sentences that sound similar — so focus on tone and context.

🔹 Modal + Passive: Should be completed, Must be submitted

TOEIC frequently includes modals in passive voice to test compound grammar understanding.

Examples:

  • “All reports must be submitted by Friday.”

  • “The shipment should be delivered tomorrow.”

Always watch for:
modal + be + past participle

🔹 Typical TOEIC Part 5 Example

The documents ___ be signed by a supervisor before submission.
a) can 

b) must 

c) should 

d) may

✅ Correct answer: b) must — It’s a clear rule, not a suggestion or option.

🔚 Final Takeaway

Modal verbs might be short, but they carry weight.
In TOEIC, they’re used to test logic, tone, and nuance — and are often paired with traps like passive voice or misleading time references.

Understanding modals helps you sound more natural, more professional, and more accurate — in both the test and the real world.

🔒 HIDDEN FAQ — MODALS (EN) Q1. What’s the difference between “must” and “have to”? A1. “Must” often expresses internal or personal obligation. “Have to” usually refers to external rules or laws. Q2. When should I use “should” instead of “must”? A2. Use “should” for advice or recommendations. Use “must” when something is necessary or required. Q3. Can I use “could” in the present tense? A3. Yes. “Could” is used for polite suggestions or possibilities in the present: “You could check with HR.” Q4. What’s the correct form after a modal verb? A4. Always use the base form of the main verb after a modal: “should go,” not “should goes” or “should went.” Q5. How do I know when to use “may” vs. “might”? A5. Both express possibility, but “may” is slightly stronger or more formal. TOEIC accepts either unless tone matters. Q6. Can modals be used in the passive voice? A6. Yes. The structure is: modal + be + past participle. Example: “The report must be submitted.” Q7. What’s the difference between “can” and “could” for ability? A7. “Can” is for present/future ability. “Could” is for past ability or more polite suggestions. Q8. Is “ought to” commonly used on TOEIC? A8. It appears occasionally, usually in Part 5, but “should” is much more common and acceptable. Q9. Are modals ever followed by “to”? A9. Most modals are not. But exceptions like “ought to,” “have to,” and “be supposed to” do require “to.” Q10. Do modal verbs change form for different subjects? A10. No. Modals are fixed — no -s, -ed, or -ing. You say “He can go,” not “He cans go.”