Duolingo English Test Practice Test 1

Someone has spilled orange juice all over the kitchen floor, and I am fairly su it was the twins. Mateo can name every planet, every moon, and nearly every star visible from his balc. Rabbits, unlike most rodents, have long ears that also help them lose heat on hot sum days. Experienced editors know that cutting a sentence in half often impr it, although writers seldom believe this at first. Suppose you could speak to anyone in history for an hour; whom would you choose, and what would you disc? Scattered across the desert floor, the ruins of a forgotten fortress sugg that a great city once flourished here.

Long before the internet, some of the greatest libraries in the ancient world tried to collect all human knowledge in one place. Scho in the city of Alexandria reportedly searched every ship that doc in the harbour, copying any book on board before returning the original to its owner. Fires, wars, and simple negl destroyed many of these early collec, meaning that countless works from the ancient world survive today only as fragm or brief ment in other texts. Modern archi now digi fragile manuscripts precisely so that a single disa can no longer erase centuries of reco thought.

In the summer of 1928, the Scottish scientist Alexander Fleming left for a holiday without tidying his laboratory, a habit that colleagues often complained about. Among the untidy dishes he left behind were several samples of bacteria he had been growing to study infection. When he returned in September, Fleming noticed that one dish had been contaminated by a blue-green mould, and that the bacteria near the mould had been destroyed completely. Most scientists would have simply cleaned and reused the dish, but Fleming's curiosity was caught. He identified the mould as a type of Penicillium and discovered that it produced a substance capable of killing several kinds of dangerous bacteria without harming human cells. Fleming published his findings, yet for over a decade the discovery attracted little attention, partly because producing the substance in useful quantities Select…provedproveproving extremely difficult. Notebooks from the time show Fleming Select…consideredconsiderconsidering other explanations first. It was not until the early 1940s, when a team at Oxford led by Howard Florey and Ernst Chain found a way to purify and mass-produce it, that penicillin became a practical medicine. Its arrival transformed the treatment of wounded soldiers during the Second World War, saving countless lives that would previously have been lost to infection. Colleagues later Select…recalledrecallrecalling the incident as pure chance. Fleming, ever modest, insisted that luck had Select…playedplayplays as large a part as skill.