过去时：How did your grandfather get to the train station?
将来时：How would your grandfather go to the train station?
还可以说：In which way did(would) your grandfather go to the train station?
过去时：How did your grandfather get to the train station?
将来时：How would your grandfather go to the train station?
还可以说：In which way did(would) your grandfather go to the train station?