The Nile River Valley Though the verdant green course of the Nile Valley appears to be the very antithesis of the bleached Saharan sands through which it flows, these two contras...

综合写作： 写作真题第220套（rs140）听力音频 https://mp.weixin.qq.com/s?__biz=MzI2NzA4MDMwNA==&mid=2247522646&idx=2&sn=53dbb4dd42ea2b93e84521f827a69eae&scene=21#...

Life on Mars Astronomers strongly suspect that Mars currently has no liquid water, diminishing the chances for life there now. But running water and a denser atmosphere in the pas...

The Search for the Origins of Writing     Who invented the first writing? Like many questions of its type in archaeology, this one is not easily answered. Some might arg...

Agricultural Origins   It is tempting to think that people started domesticating plants and animals because hunting and gathering was laborious and then someone had the brilli...

The History and Composition of Laundry Detergent     The earliest ancient people used plain water for cleaning. Water can dissolve different kinds of substances and then...

The Greek City-States: Sparta and Athens Of the hundreds of city-states that evolved during the Archaic Age, (800- 479 B.C.), Sparta and Athens stand out for their vividly contras...

The Azolla Event     During the early Eocene period, about 56 million years ago, Earth's atmosphere had high levels of carbon dioxide(CO2) which warmed the planet. But a...

TF阅读真题第851篇The Rise and Spread of Japanese Woodblock Prints

The American Hospital     Few institutions have undergone as radical a transformation as the hospital has in its modern history. It is perhaps distinctive among social i...