A blanket of something such as snow is a continuous layer of it which hides what is below or beyond it.
覆盖层
If something such as snow blankets an area, it covers it.
覆盖 • More than a foot of snow blanketed parts of Michigan. 一英尺多厚的白雪覆盖了密歇根州的部分地区。
You use blanket to describe something when you want to emphasize that it affects or refers to every person or thing in a group, without any exceptions.
适用于全体的