区别主系表与被动语态

问题描述:

区别主系表与被动语态
The two continents were once joined.

被动语态是:主语+be+过去分词+by...The mountain is covered by the big snow.He was injured by a big stone主系表结构:主语+be+过去分词(后面没有by.)The mountain is covered with snow.He was injured in th...