Express ability, obligation, advice, permission, and probability with modal verbs. Each guide covers the rules, nuances, and common mistakes for can, could, must, should, may, might, and more.
Can and could are the two core modal verbs for expressing ability in English. After this page you will know how to use them for present and past ability, polite requests, and theoretical possibility — and you will never confuse could with was able to again.
Three modal verbs — may, can, and could — all express permission in English, but they are not always interchangeable. After this page you will know which one to use when, how to give and refuse permission correctly, and how to avoid the critical can't vs don't have to confusion.
Both must and have to express obligation in English, but they are not interchangeable — one comes from inside, the other from outside. After this page you will know which to use when, how to express prohibition and no-obligation correctly, and why must needs a substitute in the past and future.
Should and ought to are the two core modal expressions for giving advice and recommendations in English. After this page you will know how to use them to give advice, express expectations, criticise with shouldn't, and talk about past regret or criticism with should have.
Modal verbs let you do more than state facts — they let you reason out loud. After this page you will know how to use must for strong deduction, can't for near-certain negation, and may, might, and could for expressing possibility in the present, past, and future.
One structural pattern — modal + have + past participle — unlocks seven distinct meanings in English. After this page you will command the full system: past deduction, unrealised past possibility, regret, criticism, and unnecessary past action.