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　　Scientist Florence Wambugu works with farmers in Kenya, a country in East Africa．She helps them grow bigger and better crops．Wambugu is especially interested in finding simple ways to produce more food．

　　In the past ten years, Wambugu has spent much of her time studying sweet potatoes, which are an important food in her part of Kenya．A virus(病毒)kept attacking the plants．It stopped the sweet potatoes from growing well．Because of the virus, some farmers lost three quarters of their crops．

　　Wambugu went to war against the virus．Her research for a way to save the sweet potatoes led to a lab in St．Louis, Missouri．

　　The lab mainly works on genes(基因), the chemical “computer programs” found in the cells of living things．Genes tell a plant to produce pink flowers or an animal to grow black hair．Now scientists have found ways to move genes from one living thing to another．That process is called genetic engineering．

　　Wambugu spent three years in the lab．As a result, she created a sweet potato plant that could fight off the virus．Wambugu tested her research in Kenya, and her plants produced wonderful sweet potatoes．

　　That’s just the beginning, Wambugu believes．Genetically modified(转基因的)foods, she thinks, could help farmers in poor countries grow badly needed crops, thus, fewer people will go hungry．

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　　The ringing of the phone runs through my head, telling me someone needs help．I pick it up and 　　1　　 the routine, “Teen Lifeline, this is Amber．” About 45 minutes later I hang up, feeling pleased because I’ve helped another teen．Volunteering at Teen Lifeline has helped me realize how to deal with my own 　　2　　 and help others．

　　“My mom is always fighting with me．I want to run away．” Some teens feel their 　　3　　 is a prison, rather than a place of shelter and safety．They feel parents are only there to make their lives 　　4　　．We try to help the teens realize the danger they could be in 　　5　　 giving them advice．All we can do is to ask questions．We also try to find out where the teens would go and how they would survive．We give them a phone number if they 　　6　　 don’t want to live in their “prison”．

　　“I don’t want to 　　7　　 any more” is something we hear, and suicide(自杀)calls are some of the hardest to 　　8　　．We try to discover why they want to take their lives and how serious they are by asking them to rate it on a scale of one to ten．One means they are 　　9　　 suicide but haven’t decided how, and ten means they are always thinking about it and have a 　　10　　．We ask them to make a promise that they will not hurt themselves．And sometimes we ask for their telephone numbers 　　11　　 we can call back to make sure that they are okay．

　　Although many calls are about relatively 　　12　　 problems, volunteering at Teen Lifeline has helped me realize I’m not the 　　13　　 person with problems, and has taught me how to 　　14　　 with my heart．I have made a 　　15　　 and saved many lives－possibly even my own, too．