Question

define modal and their types and its use

Answer 1

As we already know, modal or modal auxiliaries help modify the meanings of the main verb, They combine with main verbs to show possibility, ability, duty, habit etc.
The modal auxiliaries include verb such as Cam, could, may, might, must, shall, should, will, would etc.

Answer 2

modal auxiliary verbs include : can , could, may, might, must , ought , shall , should , will and would. These verbs which never change forms the way most other verbs do - indicate , possibility ,capability, necessity or willingness.