SHOULD
CAN
MUST
What are Modal verbs?
Modal verbs are a special kind of auxiliary or helping verb. A modal verb helps the main
verb to express the mood of the subject and at the same time it can indicate possibility,
persuasion, ability, willingness, etc.
Examples of modal verbs are:
Can
Could
May
Might
Must
Should
Will
Would
Modal verbs can be used before a verb in simple form.
Examples:
I can swim.
We must hurry.
Birds can fly.
Past tense of SHALL
used in auxiliary function to express condition
if he should leave his father, his father would die
used in auxiliary function to express obligation, propriety, or expediency
I should do
should brush your teeth after each meal
used in auxiliary function to express futurity from a point of view in the past
realized that she should have to do most of her farm work before sunrise— Ellen Glasgow
used in auxiliary function to express what is probable or expected
with an early start, they should be here by noon
used in auxiliary function to express a request in a polite manner or to soften direct statement
I should suggest that a guide … is the first essential