TENSES OF VERB

The following table illustrates the proper use of verb tenses:

Simple Present	Simple Past	Simple Future
I read nearly every day.	Last night, I read an entire novel.	I will read as much as I can this year.
Present Continuous	Past Continuous	Future Continuous
I am reading Shakespeare at the moment.	I was reading Edgar Allan Poe last night.	I will be reading Nathaniel Hawthorne soon.
Present Perfect	Past Perfect	Future Perfect
I have read so many books I can’t keep count.	I had read at least 100 books by the time I was twelve.	I will have read at least 500 books by the end of the year.
Present Perfect Continuous	Past Perfect Continuous	Future Perfect Continuous
I have been reading since I was four years old.	I had been reading for at least a year before my sister learned to read.	I will have been reading for at least two hours before dinner tonight.

AA

Verb Tense	Active	Passive
Infinitive	To cook	To be cooked
Present Simple	I cook food in the kitchen.	Food is cooked in the kitchen.
Present Continuous	I am cooking  food in the kitchen.	Food is being cooked in the kitchen.
Present Perfect Simple	I have cooked food in the kitchen.	Food has been cooked in the kitchen.
Past Simple	I cooked food in the kitchen.	Food was cooked in the kitchen.
Past Continuous	I was cooking food in the kitchen.	Food was being cooked in the kitchen.
Past Perfect	I had cooked food in the kitchen.	Food had been cooked in the kitchen.
Future	I will cook food in the kitchen.	Food will be cooked in the kitchen.
Future Perfect	I will have cooked food in the kitchen.	Food will have been cooked in the kitchen.
Conditional I	I would cook food in the kitchen	Food would be cooked in the kitchen.
Conditional II	I would have cooked food in the kitchen.	Food would have been cooked in the kitchen.

Please note that the Present Perfect Continuous, the Past Perfect Continuous and the Future Continuous are not usually used in the passive form.

We use the passive form of a verb

- when the person who performs the action (agent) is unknown.

- when it is not important who does the action,or

- when we are more interested in the action that in the agent (instructions, reports, etc.)