I think the one that's most popular is that it is so deep and narrow that the sunshine only reaches most of the canyon a short time each day.

我认为最流行的一个是，因为峡谷很深，很狭窄，每天太阳只有很短的时间能够照耀到山谷的大部分。

youdao

Well, there are two theories on that. I think the one that's most popular is that it is so deep and narrow that the sunshine only reaches most of the canyon a short time each day.

关于山谷的名字，有两个理论。偶认为最流行的一个是，因为峡谷很深，很狭窄，天天太阳只有很短的时间能够照耀到山谷的大部分。

youdao