Ashok Gadgil has spent the past three decades helping people in need—and he has no plans to stop. On May 2，Gadgil won the $100，000 Lemelson-MIT Award. Each year, the honor is given to an inventor who has improved the lives of people in developing countries. Gadgil’s inventions have helped more than 100 million people around the world.
Gadgil is a professor and physicist at the University of California，Berkeley. When he’s not teaching，he works to find solutions to global problems such as energy efficiency(效率)and water safety.“I chose to focus on problems where my knowledge of science could help，”Gadgil said.
In the 1980s，he came up with a program to make energy-efficient light bulbs more affordable for people in developing countries. Then in the 1990s，Gadgil designed his first life-saving invention，UV Waterworks. It kills deadly disease-carrying germs(病菌)from drinking water. It costs just one cent to clean five liters of water. Gadgil was inspired to find an inexpensive solution to the clean water crisis after more than 10，000 people in his home country of India died from an outbreak of Bengal cholera(霍乱)，in 1993. The disease is spread through polluted food and drinking water.
So far, the invention has provided safe drinking water to more than 5 million people in India，Liberia, Nigeria，the Philippines and Ghana.
Families in refugee(难民)camps in Sudan are given food aid. But they still have to cook the meals. In order to do so，refugee women leave the safety of the camps three to five times a week to gather firewood. They walk up to seven hours a day to find enough wood to fuel their stoves. Cooking over an open flame can be dangerous to one’s health and to the environment, too，because of the amount of smoke it produces. Gadgil visited the area many times with his students and his co-workers to work with the refugee women on designing a clean，fuel-efficient stove. The Berkeley-Darfur Stove he created saves 55％ of fuel. That means the women wouldn’t have to leave the houses to find firewood as often. The invention also helps to save homes more than $300 a year. About 125，000 women and their families have been helped.
As a professor, Gadgil encourages his students to stay positive about finding solutions to hard problems.“Be optimistic when you try a hard problem，”he says.“It’s when you solve a large problem that you can have a powerful effect on the world.”
28. Gadgil was given Lemelson-MIT Award for
A. his teaching experience B. his new research report
C. his vast knowledge D. his helpful inventions
29. Which of the following is TRUE of the Berkeley-Darfur Stove?
A. It takes women 7 hours to fuel. B. It still needs the same firewood as before
C. It is clean and money-saving. D. It is equipped with a fire alarm.
30. According to the last paragraph，Gadgil encourages his students .
A. to learn lessons from failures B. to find problems in peaceful life
C. to make inventions to help poor people D. to be confident when facing difficulties31. Which of the following can best describe Gadgil?
A. Caring and optimistic. B. Powerful and positive.
C. Independent and sensitive. D. Responsible and strict.