How Did Life Begin For life to begin, it needed the right sorts of molecules, some sort of energy(such as that created by lightning), and the right environment-perhaps the 'warm l...

TF阅读真题第828篇The Growth of Industry in the United States

TF阅读真题第737篇Chinampas

TF阅读真题第791篇Pollen Gathering by Animals

TF阅读真题第806篇Maya Population in the Classic Period

TF阅读真题第719篇Did a Volcano Destroy the Minoan Civilization?

题目：     Prosperity in British North America     The British colonies of North America developed at a remarkable pace throughout the later colonial period. ...

Tidal Heating on lo     To understand tidal heating, we must go back to when the twin spacecraft Voyager 1 and Voyager 2 made close flybys of the moon lo, Jupiter's clos...

Indigo   题目： Indigo is a blue dye produced from plants of the genus group Indigofera, grown in tropical and subtropical climates, and it has been highly valued since ancie...

题目： The Fur Trade and Native Americans Soon after Europeans made contact with the aboriginal peoples of North America, known as Native Americans, trading became the focus of ...