Our teacher said the earth___(move) around the sun.
答：Our teacher said the earth moves around the sun.
译：我们老师说地球绕太阳转.
析：主过从过,时态一致,但真理不变.
尽管这里主句是过去时态.但从句是一个真理,也就是说,地球以前,现在、将来都是绕太阳转的,所以这个要用一般现在时态.