The Passive Voice

The Passive voice in English is composed by two elements : the appropriate form of the verb "to be + the past participle of the verb being discussed.
Examples :
(verb : to clean)

Subject	Verb “to be”	Past participle
Simple present: The house	Is	Cleaned everyday
Present continuous : The house	Is being	Cleaned at the moment
Simple Past: The house	Was	Cleaned yesterday
Past continuous: The house	Was  being	Cleaned last week
Present perfect : The house	Has been	Cleaned since two hours ago
Past perfect : The house	Had been	Cleaned before they arrived
Future : The house	Will be	Cleaned next week
Present conditional : The house	Would be	Cleaned if the host had visitors