1. But while the earth has slumbered,all the air has been alive with feathery flakes descending,as if some northern Ceres reigned,showering her silvery grain over all the fields.

解析:本句的主干為:all the air has been alive。While引導讓步狀語從句，意為“盡管大地還在酣睡”；介詞短語with feathery flakes descending作狀語，表示伴隨。As if意為“好像”，引導方式狀語從句；現(xiàn)在分詞短語showering..作狀語，表伴隨。

2. The snow lies warm as cotton or down upon the window-sill;the broadened sash and frosted panes admit a dim and private light,which enhances the snug cheer within.

解析:本句包含兩個簡單句,由分號隔開。分號前為第一個分句，其主干為The snow lies warm…or(lies)down upon the window-sill。第二個分句的主干為the…sash and…panes admit a…light,which至句末為定語從句修飾light，說明這光線的作用。