The Grammar Lab: Modals of Ability & Obligation

The Grammar Lab: Modals

Lesson 08: Ability & Obligation

What are Modals?

Modals are "helper verbs" that change the mood of a sentence. They show if you can do something (Ability) or if you must do something (Obligation).

💪 Ability: សមត្ថភាព

👮 Obligation: កាតព្វកិច្ច

Ability Can / Could

Use Can for now. Use Could for the past.

I can swim.	ខ្ញុំអាចហែលទឹក
She could run fast when young.	ធ្លាប់អាចរត់លឿន
I cannot (can't) drive.	មិនអាចបើកបរ

Obligation Must / Have to

Must is for strong/written rules. Have to is for facts/daily routines.

You must wear a uniform.	ត្រូវតែ (ច្បាប់)
I have to go to work.	ត្រូវទៅ (កាតព្វកិច្ច)
She has to study.	នាងត្រូវរៀន

Prohibition vs. Optional ⚠️ Critical

These two are completely different!

Mustn't	STOP! Don't do it. (Forbidden)	ហាមដាច់ខាត
Don't have to	Relax. You can do it if you want, but you don't need to.	មិនចាំបាច់ទេ

Example: "You don't have to run, but you mustn't stop completely."

Pick the Modal

Click to see the correct modal for the situation.

Skill (Now)Context

Skill (Past)Context

Rule (Forbidden)Context

Not NecessaryContext

Quick Check

1. It is a holiday! You _____ go to school.

2. When I was 5, I _____ swim.

3. This is a secret. You _____ tell anyone.