be covered by/with有什么区别？怎么用

be
covered
by意为“被……所覆盖”,是被动语态,“为……所覆盖”还可用be
covered
with来表示,但这不是被动语态,而是系表结构,注重于事物的状态,可译为“到处都是”.例：The
mountain
was
covered
with
snow
all
the
year
ro