Задание №5177 ЕГЭ по Английскому языку

Bread

Bread is always on our table like many other products. However, we                          (NOT KNOW) who invented it. Since that time bread                          (CHANGE) in many ways. For example, sliced bread                          (INTRODUCE) in 1930. New varieties of bread appear every day. There is no doubt that people will continue to experiment with flavours and tastes of bread in the future.