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Stephen Hawking, who is the most famous physicist, was born in Britain on January 8^th, 1942. As a child, he was enthusiastic about 16     (design) complicated toys but    17  (fortune), in his twenties, he suffered   18   a disease that was impossible to be cured,    19    was a great challenge for him. However, not only was he positive about the misfortunes    20     eventually he defeated all the obstacles but also he was  21  (absorb) in his research in the universe. In 1988, his best-seller A Brief History of Time was published, 22     which he put forward the idea  23   time itself has a beginning, and that it will have  24  end. In conclusion, he has made outstanding  25  (contribute) to the fields of cosmology and quantum gravity.