Modal Verb Rules
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What are Modal Verbs?
Modal verbs are auxiliary verbs (also known as helping verbs). Normally modal verbs cannot work alone and must work with the main verb.
Modal Verbs are used with ordinary verbs to express see meanings such as possibility, permission, certainly, etc.
List of the Modal Verbs in English:
Modal verbs Rules and Uses with Examples
1. Can and May
‘Can’ usually expresses ability or capacity.
- I can swim across the river.
- Can you lift this table?
‘Can’ is also used to express permission.
- You can go now.
‘May’ is a more formal modal used to express permission or possibility.
- You may come in.
- May I leave the room now?
‘May’ is also used to suggest possibility in an affirmative sentence.
- He may be at home.
- It may rain tomorrow.
‘Can’ is used to suggest possibility in negative/interrogative sentences.
- Can this be true?
- It cannot be so.
‘May’ when used in a negative sentence suggests an improbability whereas ‘can’ suggests impossibility.
- He may not come today.
- She cannot sing.
‘May’ suggests less possibility than ‘can’.
- He can hold his breath for 30 seconds (means He is able to hold his breath for 30 seconds).
- He may hold his breath for 30 seconds (means It is possible that he will hold his breath).
2. Could and Might
‘Could’ and ‘might’ are used as past forms of ‘can’ and ‘may’ respectively.
- I could swim across the river when I was young.
- I thought he might be at home.
‘Might’ suggests less possibility or probability than ‘may’.
- I may go to Mumbai next week (means I probably will go to Mumbai).
- I might go to Mumbai next week (means it’s unlikely that I’ll go to Mumbai).
‘Could’ is used as a polite form of seeking permission or making a request.
- Could you pass me the plate?
- Could I please talk to Mr. Grover?
3. Shall and Will
‘Shall’ is used with first-person and ‘will’ in all the persons to denote future action.
- I shall need the money tomorrow.
- When will you come next?
‘Shall’ is used with the second and third person to express command, promise, or threat.
- You shall never come near my child.
- You shall be punished for this.
- We shall go for a picnic this Sunday.
‘Will You’ indicates an invitation or request.
- Will you dine with us tonight?
- Will you lend me your car for a week?
4. Should and Would
‘Should’ and ‘would’ are used as past forms of ‘shall’ and ‘will’ respectively.
- I expected that I would get a first class.
- She would sit for hours listening to the radio.
‘Should’ is used to express duty or obligation.
- We should obey the laws.
- You should keep your promise.
‘Should’ is used to express a supposition.
- If it should rain, they will not come.
‘Should’ can also be used to express probability.
- He should be in the library.
‘Must’ is used to express necessity.
- You must improve your spelling.
‘Must’ is also need to express obligation, and is a stronger word than ‘should’.
- We must follow the law.
‘Must’ is also used to express logical certainty.
- Living alone in such a big city must be difficult.
‘Ought’ is used to express moral obligation and is stronger than both ‘should’ and ‘must’.
- We ought to love our parents.
‘Ought’ is also used to express probability sometimes when the probability is very strong.
- The book ought to be very useful.