The Key Factors Influencing Soil Formation   Soil is the product of the complex interplay of several factors. Weathering, a process that breaks down rocks by physical (mechani...

题目： Farming in Uruk   The ancient city of Uruk in the southern region of Sumer in the ancient Middle East developed an agricultural system that depended on irrigation to ...

TF阅读真题第677篇The Importance of Seed Plants

TF阅读真题第847篇Waking Up Coming Out of Hibernation

There is a much greater similarity between the flowering plant floras of different continents—South America, Africa, Asia, and Australia—than between the mammalian faunas  (anim...

TF阅读真题第690篇Egypt in Early World History

TF阅读真题第809篇Animal Locomotion

TF阅读真题第727篇The Ecology of Kirtland's Warbler

Dutch Art and the Middle Class     Throughout history,the wealthy have been the most avid art collectors. Indeed, the money necessary to commission leading artists to ...

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...