"We use modal auxiliary verbs in the passive voice because it sounds more objective and less personal. "

In the active voice, we start the sentence with the person who does the action.
In the passive voice, we start the sentence with the object that takes or receives the action.

Structure of sentence in Active & Passive Vioce with model auxiliaries:

• Structure of Active voice •

Subject	Modal Auxiliary	Verb	Object
She	can	cook	the food.
(She - subject)	(can - auxilary)	(cook - verb)	(food - object)

• Structure of Passive voice •

Object	Modal Auxiliary	Verb	Past Participle	Subject
The food	can	be	cooked	by her.
(The food- subject)	(can - auxilary)	(be - verb)	(cook - past participle)	(her - object)

Examples:

Auxiliaries	Tense
Am, Is, Are + Past Participle	Simple Present Tense
Was, Were + Past Participle	Simple Past Tense
Shall, Will + Past Participle	Simple Future Tense

Active Voice	Passive Voice
I	By me
We	By us
You	By you
He	By him
She	By her
It	By it
They	By them
People	By people
Ramesh	By Ramesh
Who	By whom

Examples: