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TF阅读真题第744篇The K/T Boundary
In the late 1970s, several research groups were trying to determine the cause of the boundary between the geological layers corresponding to the Cretaceous and Tertiary periods, ab...
TF阅读真题第745篇Centralized Societies: Archaeological Evidence
When studying an archaeological site, archaeologists must first try to understand how the society that lived there was organized. Some societies are centrally organized, and...
TF阅读真题第739篇The Formation of Moons
All planets in the solar system except Venus and Mercury have at least one moon orbiting them,with the two largest jovian (giant) planets,Jupiter and Saturn,each having over sixty....
