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1·Nobody, nothing, was visible except for the occasional condor, floating on a thermal updraught and watching for the tell-tale movement of prey scurrying below.

一路上无人无物，除了偶尔看到在热浪上飞掠而过的秃鹰，搜寻着下面可能因疾行而暴露踪迹的猎物。