Sentence examples for it's dark from inspiring English sources

The part of a sentence "it's dark" is correct and can be used in written English.
It is a complete sentence on its own and can be used to describe the absence of light or a lack of brightness. Example: - I can't see anything, it's dark in here. - The sky is clear and full of stars, but it's dark on the ground. - Be careful, it's dark outside and there are no streetlights.