When other nine-year-old kids were playing games, she was working at a petrol station . When other teens were studying or going out , she struggled to find a place to sleep on the street. But she overcame these terrible setbacks to win a highly competitive scholarship and gain entry to Harvard University . And her amazing story has inspired a movie , " Homeless to Harvard : The Liz Murray Story" , shown in late April . Liz Murray , a 22-year-old American girl, has been writing a real-life story of willpower and determination . Liz grew up in the shadow of two drug-addicted parents. There was never enough food or warm clothes in the house . Liz was the only member who had a job . Her mother had AIDS and died when Liz was just 15 years old. The effect of that loss became a turning point in her life. Connecting the environment in which she had grown up with how her mother had died , she decided to do something about it. Liz went back to school. She threw herself into her studies, never telling her teachers that she was homeless . At night , she lived on the streets. " _ she wrote in her book Breaking Night . She admitted that she used envy to drive herself on . She used the benefits that come easily to others , such as a safe living environment , to encourage herself that " next to nothing could hold me down". She finished high school in just two years and won a full scholarship to study at Harvard University . But Liz decided to leave her top university a couple of months earlier this year in order to take care of her father, who has also developed AIDS. " I love my parents so much . They are drug addicts. But I never forget that they loved me all the time." Liz wants moviegoers to come away with the idea that changing your life is " as simple as making a decision". The main idea of the passage is   _   .
how Liz managed to enter Harvard University What a hard time Liz had in her childhood why Liz loved her parents so much how Liz struggled to change her life