180. Quasars are so distant that their light has taken billions of years to reach the Earth; consequently, we see them as they were during the formation of the universe. (A) we see them as they were during (B) we see them as they had been during (C) we see them as if during (D) they appear to us as they did in (E) they appear to us as though in

正确答案A中为什么使用一般过去时as they were during? 是虚拟语气吗？ 先谢过诸位侠客！

No, it's not. The reason the past tense is used is only because that event, the formation of the universe, happened in the past.