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When I came home,the sweets had been eaten by them.This book was written by them in the 19th century.A number of important experiments has been made by them in this laboratory.A new president is elected by people every four years in the USA.He will be operated by the doctor in a week.Streets are being cleaned from rubbish by the workers.Very delicious food was being made by my mother when I came home.This program can be used by me in my Internet project.Two foreign languages:French and German are studied by our students.