What is a major difference between autobiographies and biographies?

Ineed badly ! i got to get this done and i can't get it done tomorrow! 1. expand the meaning of each sentence by adding adjectives. (dinner cooks.) (clown chuckled.) (car raced.) (dancer spun.) (panthers growled.) (leaves fall.) (bread baked.) (lake glistened.) (ship glides.) 2. using the sentences above, expand the meaning by adding adverbs. 3. using any five of the sentences from #2, expand the meaning by adding a compound word to each sentence. 4. using any three of the sentences from #3, expand the meaning by adding a prepositional phrase to each sentence. 5. using any one of the sentences from #4, expand the meaning by adding a synonym to this sentence.