Degradation and Erosion of Soil Land without soil can support only very small primitive plants such as lichens and mosses that can cling onto a rock surface. The rest of the worl...

  Sunspot Cycles   Dark regions on the Sun, called sunspots, were studied in 1610 by Galileo, who turned the newly invented telescope on objects in the sky. A lively deba...

TF阅读真题第798篇Transportation and the Roman Empire

Animal Farming in the Chesapeake Colonies The Chesapeake colonies were established by English settlers near Chesapeake Bay in North America in the seventeenth century. Tobacco pr...

TF阅读真题第808篇Effects of Plate Tectonics on Species

TF阅读真题第814篇Agriculture in Colonial New England

  Making the Most of Dark Nights       The main breeding station of the marine bird known as the swallow-tailed gull is the Galápagos Islands, which straddle...

Horns in Beetle Competition       Intraspecific competition-that is, competition between members of the same species for limited resources-can be a complex phenome...

Science and Nineteenth-Century Visual Arts     In the middle of the nineteenth century, rapid developments in the sciences and popular fascination with recent technologi...

  Part 1 READING PASSAGE 1 Read the text on the next page and answer Questions 1-13. Prison: The Solution or the Problem? In the Netherlands and parts of the USA such as Jo...