Modal verb a modal verb is a kind of auxiliary verb that is used to express modalities (the states or ‘modes’ in which a thing exists) such as possibility, ability, prohibition and necessity

Can - I can jump.

Could - We could go to the cinema tomorrow.

May - They may be coming to our house tomorrow.

Might - It might rain on Friday.

Should - You should tell him.

Shall - If it’s dry, shall we play outside?

Will - I will try my best.

Would - My parents wouldn’t give me any pocket money.

Must - You must be quiet.

Have - I have to see the doctor about my leg.

It’s important to give students context for new words and grammar rules. Using modal verbs examples, like the ones above, demonstrates sentence structure and provides real world meaning to what they are learning. Plus, you can’t see the effect a modal verb has without knowing the verb it is working with and the rest of the sentence it’s a part of!
When teaching or introducing modal verbs, you could list out these main modal verbs for your class and then have them discuss which words are the most important, and which are less convincing. You can use these nine modal verbs examples, to make the activity less challenging. This will help them realise that they might already understand how modality works - they just didn’t have a name for it yet!
Once they are confident with how modality can be used in a sentence, have your students write their own list of modal verbs examples. This will make the different modal verbs easier to remember and gives students important writing practise to help them structure their sentences. Writing their own examples will help the students’ understanding of grammar and build their communication skills.

Why are modal verbs important?
Modal verbs allow us to quickly give more detail about an action in a sentence. As a kind of auxiliary verb, modal verbs are useful for helping us communicate more clearly.
These words are often used in instructions, rules and guides - all areas where being precise and commanding are important. Knowing the difference between ‘must’ and ‘might’ will help the reader make a mental note of the importance of an instruction. This makes us better communicators in our day-to-day life.
Not just that, but having full grasp of this topic will allow young language learners to be more particular about the words they use, which will improve their ability to communicate with others.