Covered = To place something upon or over, so as to protect or conceal; To overlay or spread with something; To put a cover or covering on.
Synonyms: wrapped up, enclosed, roofed, masked, coated.
Example – Their faces will never be covered with shame.
Usage in Sentence: Covered with, not by.
Don’t say: The mountains are covered by snow.
ü Say: The mountains are covered with/in by snow.