Modal Verbs List and Using in English
| CAN | Ability, doubt, astonishment, permission, Polite request |
| MAY | Permission, if not prohibition, supposition with doubt |
| MUST | Obligation, firm necessity, logical conclusion, probability |
| SHALL | intention, supposition |
| WILL | Wish, desire, will, confidence, in the future |
| OUGHT TO | Moral duty, insistent advice, strict recommendation |
| NEED | (un)necessity |
| BE TO | Obligation arising out of arrangement or agreement |
| HAVE TO | Unwillingness, forced circumtances |
| WOULD | Wish (with “to like”), polite request, a habit of the past |
| SHOULD | Necessity, advice, blame, recommendation, reproach, regret |
| USED TO | Repeated action in the past |
