Modal Verbs — Expressing nuances in English
Modal verbs add extra meaning to the main verb: ability, possibility, obligation, permission, advice...
Modals by function
| Function | Modal | Ejemplo |
|---|---|---|
| Habilidad | can, could | I can swim. / I could swim when I was 5. |
| Posibilidad | may, might, could | It might rain tomorrow. |
| Permiso | can, may, could | May I use your phone? |
| Obligation | must, have to | You must wear a seatbelt. |
| Prohibition | mustn't, can't | You mustn't smoke here. |
| Consejo | should, ought to | You should see a doctor. |
| No necesario | don't have to | You don't have to come. |
⚠️ Diferencias sutiles
| Contraste | Explanation |
|---|---|
| must vs have to | must = personal obligation; have to = external obligation |
| mustn't vs don't have to | mustn't = forbidden; don't have to = it is not necessary |
| can vs may | can = informal; may = formal (for permission) |
| should vs must | should = advice; must = strong obligation |
Strength scale
must > should > could > might (from strongest to weakest)
💡 Remember: Modals DO NOT change with the person (he can ✓,
he cans✗) and are followed by the verb in base form (must go ✓,must goes✗).