1.   Archeologists are beginning to think they have been underestimating the early Stone Age ancestors of modern human beings.

2.   Archeologists have therefore begun to rely on other high-technology imaging techniques, like satellite-based radar, to peer into the earth.

3.   As it is, the archeologists have just begun to explore the site.

4.   But archeologists began formally exploring the underground caves a year ago.

5.   But this rich, vain and often mendacious amateur archeologist also began another tale of greed and national honor that reverberated for more than a century.

6.   Its ruins disappeared in the desert until archeologists began digging there in this century.

7.   The archeologists began their work at Zhongbaodao because it was among the sites scheduled to be destroyed as a result of the construction work on the dam.