Modals (The Mood Makers)

🔑 Key Concept

Modals are auxiliary verbs that express necessity, possibility, ability, or permission. They never change form (no 's', 'ing', or 'ed').

1. Ability & Capacity

Modal	Usage	Example
Can	Present Ability / Informal Permission	I can swim across the river.
Could	Past Ability / Polite Request	He could run fast when he was young.

2. Permission & Possibility

Modal	Usage	Example
May	Formal Permission / High Possibility	May I come in, sir? It may rain today.
Might	Remote (Low) Possibility	He is sick, but he might come.

3. Obligation, Advice & Necessity

Modal	Usage	Example
Should	Advice / Suggestion (Mild)	You should respect your elders.
Must	Compulsion / Strong Necessity	You must wear a helmet.
Ought to	Moral Duty (Formal)	We ought to help the poor.

⚠️ Common Confusions (Exam Hack)

Can vs May (Permission): Use "Can" for friends, "May" for teachers/elders.
Should vs Must (Advice): "Should" is a good idea; "Must" is a rule/law.
Will vs Shall: Modern English uses "Will" for almost everything. "Shall" is used for suggestions (Shall we dance?) or formal commands.

📝 Practice Examples

___________ you please pass the salt? (Polite Request)
Answer: Could or Would.
Candidates ___________ answer all questions. (Compulsion)
Answer: must.
It is cloudy. It ___________ rain. (Possibility)
Answer: may.

🔥 Teacher's Secret: Modal Traps!

The "Can Able To" Error: Never use "can" and "able to" together.
Wrong: I can be able to do it.
Right: I can do it. OR I am able to do it.
Modals + V₁ Only: Never add 's', 'ed', or 'ing' to the main verb after a modal.
Wrong: She can sings.
Right: She can sing.
Must vs Have to:
Must: Internal obligation (I feel I must do it).
Have to: External obligation (Rules/Others say I have to).