历史学家认为，印加人在1450年始围绕马丘·比丘，而是因为他们没有留下任何文字记载的背后，没有人确切地知道他们的目的是什么。

Historians believe the Inca began building Machu Picchu around the 1450s, but because they left no written records behind, no one knows exactly what their purpose was.

youdao

历史学家认为，印加人在1450年代开始建立马丘·比丘，但是因为他们没有留下任何文字记载，所以没有人确切地知道他们的目的是什么。

Historians believe the Inca began building Machu Picchu around the 1450s, but because they left no written records behind, no one knows exactly what their purpose was.

youdao