When the sky is clear, the sun and the stars help to guide the course, and if they are followed one is saved from traveling in a circle, as the lost are pretty sure to do in a dense forest.
【正确答案】：当天空很晴朗的时候，太阳和星星可以指明方向。在茂密的树林里，迷路者经常会在原地绕圈而走不出去。如果跟着它们，就会避免绕圈。
【题目解析】：they are followed中的they指的是the sun and the stars。