Modal Verbs

Facts about modal verbs:
They function as special verbs that do not follow the rules applied to other normal verbs.
Modal verbs to not take “-s” in the third person (present simple)
She shoulds should study more.

They do not take “-ed” nor “-ing” endings.  In fact, most of the modal verbs do not have  a past, continuous or future form.
We musted must always do our best.

They do not need auxiliary verbs to form negative or interrogative sentences.
Do you can speak Japanese?
Can you speak Japanese?

Each modal verb can have more than one meaning. Moreover, the same meaning can be expressed by different modals. Study the following examples:
It may rain tonight.    (It is possible to rain)
May I watch television?    (Do I have the permission to watch television)
Can you speak Japanese?    (Do you have the ability to speak Japanese?)
Can I leave the room?    (Do I have the permission to leave the room?)
Maybe we can go to the cinema tonight.   (There is a possibility of going to the cinema)
Can you help me?   (I am requesting your help)

Now that we have covered some of the basic rules of modal verb usage let’s look at them more closely.
Modal Verbs Chart

Let’s practise some more.
Modal Verbs Exercise
Modal Verbs 2