The document discusses the key differences between active and passive voice in sentences. In passive voice, the object becomes the subject and the subject is mentioned using "by". The main verb is always the past participle form, and auxiliary verbs are used to indicate the tense. Examples are provided to illustrate active and passive transformations for different tenses including present, past, future, perfect, and continuous forms. Special cases like intransitive verbs are also mentioned.

7. • The places of subject and object are interchange.
• Some time subject of the sentence may not used in
passive voice.
• 3rd form of verb is always used as main verb in
sentence of passive voice for all tenses.
• Auxiliary verbs are used in passive voice according to
the tense of sentence.

8. Active voice: Subject + form of the verb + object
Passive voice: Object + be + past participle + by + subject

9. • Somebody steel my beg. Active
• My beg is stolen. Passive
• My beg is stolen by somebody. Passive
• I am writing a letter. Active
• A letter is being written by me. Passive
• A letter is being written. Passive

10. • She has finished her work Active
• Her work has been finished by her passive
• I killed a snake Active
• A snake was killed by me passive
• He was driving a car Active
• A car was being driven by him passive
• They had completed the work active
• The work had been completed by them p

11.  Present perfect continuous tense
 Past perfect continuous tense
 Future continuous tense
 Future perfect continuous tense
 Sentence having Intransitive verbs