Passive Voice 

 Use:

Passive voice is used when the focus is on the action. It is not important or not known, however, who or what is performing the action. The passive voice is a grammatical construction (specifically, a "voice") in which the subject of a sentence or clause denotes the recipient of the action (the patient) rather than the performer (the agent).  Passive voice is formed with an auxiliary verb (usually be or get) plus a participle (usually the past participle) of a transitive verb.

Example:

TENSE	Active	Passive
Simple Present	He writes a letter	A letter is written by him
Simple Past	He wrote a letter	A letter was written by him
Present Progressive	He is writing a letter	A letter is being writing by him
Past Progressive	He was writing a letter	A letter was being written by him
Present Perfect	He has written a letter	A letter has been written by him
Past Perfect	He had written a letter	A letter had been written by him
Future with Will	He will write a letter	A letter will be written by him
Future with going to	He is going to write a letter	A letter is going to be written by him
Conditional	He would write a letter	A letter would be written by him
Hilfsverben	He can write a letter	A letter can be written by him

Active Voice

In active voice focuses mainly PERSON PERFORMING AN ACTION

Tom writes a letter

Tom is writing a letter

Tom was writing a letter

Tom wrote a letter

Tom has written a letter

Tom had written a letter

Tom will write a letter

Tom is going to write a letter

Tom can write a letter

Tom could write a letter

Tom must write a letter

Tom may write a letter

Tom might write a letter

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