What causes the moon to be darkened in a lunar eclipse?

The sun rays are blocked from reaching the moon.

Explanation:

The earth lies in between the sun and the moon.

Since the earth is in the middle, the sun rays are blocked from reaching the moon, hence dark.

the moon does not have any light of its own it shines because its surface reflects sunlight. during a total lunar eclipse the earth moves between the sun and the moon and cuts of the moon's light supply when this happens the surface of the moon takes a reddish glow instead of going completely dark