The passive of an active tense is formed by putting the verb 'to be' into the same tense as the active verb and adding the past participle of the active verb. The subject of the active verb becomes the 'agent' of the passive verb. The agent is very often not mentioned. When it is mentioned it is preceded by 'by' and placed at the end of the clause. A] Examples of present, past and perfect passive tense: Ex: 1] My grandfather planted this tree. (Active) This tree was planted by my grandfather. (Passive) 2] We keep the butter here. (Active) The butter is kept here. (Passive) 3] They broke the window. (Active) The window was broken. (Passive) B] The passive of continuous tenses requires the present continuous forms of 'to be', which are not otherwise much used: 1] They are repairing the bridge. The bridge is being repaired. C] Auxiliary + infinitive combinations are made passive by using a passive infinitive: 1] You must shut these doors. (Active) These doors must be shut. (Passive)

In English you often use the active voice as well. You will many times say: Peter stole my car Dario asked a question Maria wrote a letter. The passive voice is used when mentioning the subject of the sentence ( Peter,Dario ,Maria in the above examples) is of little significance in the context and the emphasize is more on the action itself (stole, asked ,wrote in the above). The sentence might have some additional information that is crucial to mention as in: "The car was stolen last week ,while Dario was away on vacation." Here there is other important information to convey,while the thief ,the wrongdoer is of no importance and wouldn't make a difference to mention in this particular context. There are other reasons to use the passive voice like not wanting to mention the person who did something , or referring to something that is done by many people habitually as in: " In Spanish the active voice is more often used." 'is used' here is a passive form,the active one would be: "In Spanish people more often use the active voice." The passive voice is formed as follows: verb to be ( in the tense equivalent to that used in the active voice sentence) + the main verb in the participle. Examples: He writes the letter. ( simple present) The letter IS written ( to be in simple present + participle of verb 'to write') He stole the car ( past simple) The car WAS stolen ( to be in past simple tense + participle of 'steal') He has just given me the answer.( present perfect) The answer has been just given. ( to be in present perfect) She will give a lecture next week.( future tense) A lexture will be given next week. (to be in future tense) etc.... Notice that when forming the passive sentence you can possibly add the omitted subject at the end through the form ( by + subject) as in: "The car was stolen BY Dario." "The letter was written by her." In most cases it is redundant though and no need to mention the subject at all. That is an overall idea about the passive form in English, hope it answers your question~!

Active voice stresses on "who acts or does the action" while passive voice focuses on the action. Normally, the action comes first than the doer of the action if passive voice is used and what or who does the actions is generally not important in this case. To convert sentences in active voice to passive here are a few notes: -The direct object usually comes first. A direct object is a noun or pronoun that receives the action. It typically answers "what" or "whom". -The past participle form of the verb is used. -The doer of the action follow the verb, or is dropped. It follows this simple pattern: Direct object + verb, past participle + by doer Active: Peter stole my car. Passive: My car was stolen by Peter.

You use the passive when you want to show that the actio of the verb is more important than the agent.The agent is introduced with the preposition "by" and is mentioned only when it is important or needs to be stated.(Oliwer Twist was written by Charles Dickens) The agent is not mentioned when: it is unknown(His car was stolen las night.) it is unimportant(Breakfast will be served at 7a.m.) it is obvious from the context(He has been arrested.)

Passive voice is tricky, yes. You may need more than just a single example to understand it an be able to use it.