蝙蝠们遇到了一个技术上的难题：如何在没有光线的条件下认路和捕食。

Bats have an engineering problem: how to find their way and find their prey in the absence of light.

youdao

这是生活的一部分，旅行时，我们会遇到一些风景优美的小径，但是光线暗淡。

It's part of life. When traveling, we will meet some paths that are scenic, some paths that are just blank.

youdao

这是生活的一部分，旅行时，我们会遇到一些风景优美的小径，但是光线暗淡。

It's part of life.When traveling, we will meet some paths that are scenic, some paths that are just blank.

youdao