TOEIC Grammar Trap · Part 5

TOEIC Modal Verbs: Can, Could, Should, Must, May, and Might

TOEIC modal questions are not only grammar questions. They test tone, obligation, possibility, permission, and business logic.

This is the main modal verbs guide. For deeper patterns such as passive modals, polite business requests, have to, and be supposed to, continue to TOEIC Modal Verbs Part 2.

Employees must wear ID badges in the building.

You should review the report before sending it.

The shipment may be delayed because of bad weather.

Could you send the file by noon?

Core TOEIC rule: Do not choose only by meaning. Ask whether the sentence needs a rule, advice, possibility, permission, or polite request.

The 7-second choice

When TOEIC gives you modal choices, first name the business situation.

Rule / requirementmust, have to
Advice / recommendationshould, ought to
Possibilitymay, might, could
Abilitycan, could
Permissioncan, may
Polite requestcould you, would you

Must: strong rule or requirement

Use must when the sentence shows a strong requirement. In TOEIC business English, this often appears with rules, forms, deadlines, safety, and company policy.

All visitors must sign in at reception.

Applications must be submitted by Friday.

Employees must follow the safety instructions.

Fast check: if the sentence sounds like a rule, not advice, must is often the safer direction.

Should: advice or expected action

Use should when the sentence gives advice, a recommendation, or an expected action that is not as strong as a rule.

You should double-check the figures before the meeting.

The team should arrive at least ten minutes early.

Applicants should attach a copy of their résumé.

Fast check: if the sentence feels like a recommendation, not a strict requirement, check should.

Can and could: ability, possibility, and polite requests

Can often shows ability or ordinary possibility. Could can show past ability, weaker possibility, or a more polite request.

The software can process invoices automatically.

The old system could handle only 200 orders per day.

Could you send the revised schedule?

Fast check: if the sentence is a polite business request, could you is often safer than can you.

May and might: possibility

May and might often show possibility. May can also sound more formal when asking for permission.

The delivery may arrive this afternoon.

The meeting might be postponed.

May I speak with the manager?

Fast check: if the sentence is uncertain, check possibility. If the sentence is formal permission, check may.

Common TOEIC business signals

by Fridaydeadline or requirement
company policyrule or obligation
please / could youpolite request
be delayedpossibility
recommendedadvice
is able toability

Small words around the blank matter

TOEIC often gives the answer through the tone of the sentence.

The documents ___ be signed by a supervisor before submission.

Signal: before submission → required process.

Answer direction: must.

You ___ review the figures before presenting them.

Signal: advice / safer action.

Answer direction: should.

Quick TOEIC check

1. All visitors ___ wear identification badges inside the facility.

2. You ___ review the contract before signing it.

3. The new software ___ process invoices automatically.

4. The delivery ___ be delayed because of the storm.

Fast-reader mistake

Fast readers often choose the modal they recognise first. But TOEIC tests the role of the sentence: rule, advice, possibility, permission, request, or ability.

Bad shortcut: “This modal sounds familiar.”

Better shortcut: “What business tone does the sentence need?”

Why this mistake returns under pressure

Under time pressure, modals look small and easy. That is why they are dangerous. The answer often depends on one small signal: deadline, rule, uncertainty, request, or recommendation.

One-second tool

Use this shortcut:

Strict rule → must

Advice → should

Ability → can / could

Possibility → may / might / could

Formal permission → may

Polite request → could you / would you

Final takeaway

TOEIC modal questions are business-tone questions. Do not ask only, “What does this modal mean?” Ask, “What kind of business situation is this sentence showing?”

Name the tone, choose the modal, and move on.

🔒 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.