Нужно ответить по- на вопросы: what discoveries in the history of mankind do you regard as breakthroughs? what inventions in the history of mankind do you regard as most important? which of the centuries in your opinion saw the greatest inventions and discoveries?

1.I belong to the important discoveries of mankind there is a fire, the wheel, writing, paper, gunpowder and firearms, telephone, telegraph, radio, internet, car light bulb, antibiotics, and a sail ship.2.I think the ax, bow and arrows, and a paddle boat.3.I think 15th century.