明朝在“外边”长城之外，还修筑了“内边”长城和“内三关”长城。

Ming Dynasty in "outside" outside Great Wall, but also has constructed "in side" the Great Wall and "in three passes" the Great Wall.

youdao

明朝在“外边”长城之外，还修筑了“内边”长城和“内三关”长城。

Ming Dynasty in "outside" outside Great Wall, but also has constructed "in side" the Great Wall and "in three passes" the Great Wall.

youdao