Uses of Modal Auxiliary Verb
1. Can:
| Ability | I can walk ten miles at a time. |
| permission | You can go. |
| Seek permission | Can I talk to you? |
| Possibility | I can go to your house. |
| Request | Can you help me with some money? |
2. May
| Possibility (less than can) | He may come to my house. |
| Seek permission gently | May I come in? |
| Purpose (present) | He works hard so that he may prosper in life. |
| Wishes and hopes | May Bangladesh long live. |
| Speculation | They may be waiting at the station for you now. |
| Give permission (2nd and 3rd person) | You may go now. |
3. Could
| Past ability/ habitual work | I could walk ten miles at a stretch. |
| Polite Request | Could you help me? |
| Past inability | I could not understand you. |
| Suggestion | You could talk to the Principal. |
4. Could have
| Someone could do a work but did not do | You could have done the sum. |
5. Might
| Possibility (less than 'may) | He might leave the country. |
| Purpose (Past) | He worked hard so that he might prosper in life |
| Speculation | They might be playing now. |
- Shall
| Future event (I,We) | We shall go out for a visit. |
| Command, threat, Authoritative order (2nd,3rd person) | You shall Carry out my order. |
| Intention of the speaker | You shall have a nice pen. |
| Determination | The weak shall be given equal rights. |
7. Should
| Obligation/Duty | We should obey our parents |
| Advice/ recommendation | You should stop smoking. |
| Polite request | Shall I help you? |
| Use after ‘Lest’ | He walked fast lest he should miss the train. |
| Assumption in present, past and future tense | It should be raining now. He should have reached home by now. He should have much time to reach the station. |
| Past obligation | He should have read sincerely. |
8. Will
| Future action | You will do the work. |
| Future prediction | He will start a school very soon. |
| Order (2nd and 3rd person) | You will carry out my order. |
| Determination (1st person) | I will do the work at any cost. |
| Polite request (2nd person) | Will you post the letter for me? |
| Future habitual action | Spring will come again. |
| Conditional | If you want, I will help you. |
9. Would
| Polite request | Would you post the letter for me? |
| Offer/invitations | Would you mind having a cup of tea with me? |
| Purpose( after ‘in order that’ and ‘so that’) | He worked hard in order that he would shine in life. |
| Conditional (past) | If you wanted, I would help you. |
| Preference (would rather/would better/would sooner) | He would rather die than beg. |
10. Must
| Obligation | You must obey your teacher. |
| Advice | You must take regular exercise. |
| Logical conclusion | You must be hungry after a long journey. |
| Certainty | He must be a good boy. |
| Determination | I must see him punished. |
| Past certainty | You must have gone there. |
11. Have to
| Obligation (have to, has to, had to shall have to/ will have to) | I have to look after my old parents. |
| Indicating advice | You have to learn English. |
12. Need
| Modal ( need not) | He need not do it. |
| Principal (need) | He needs to do it. |
13. Dare
| Modal verb(negative/interrogative) | He dare not do it. |
| Principal verb (affirmative) | He dared to go there |
| Challenge | He dares me to do the work. |
14. Used to
| Discontinued habit | I used to drink tea; now I drink coffee. |
| Continued habit | Omar (R) used to lead a very simple life. |
15. “Be” used as Modal Verb
| Duty or necessity (Am to/ is to/ are to) | I am to look after my old parents. |
16. Going to
| For future intention | They are going to open a bank account. |
17. Had better
| Preference | You had better go now. |
